Use of osteopontin for the treatment and/or prevention of neurologic diseases

ABSTRACT

The invention relates to the use of osteopontin, or of an agonist of osteopontin activity, for treatment or prevention of a neurologic diseases.

This application is a national stage application of PCT/EP02/05081,filed May 8, 2002, which claims foreign priority to European application01111296.8, filed May 17, 2001.

FIELD OF THE INVENTION

The present invention is generally in the field of neurologic diseasesand disorders. It relates to neuroprotection, nerve myelination andgeneration or regeneration of myelin producing cells. In particular, itrelates to demyelinating and neurodegenerative diseases, neuropathies,traumatic nerve injury, stoke and neurologic diseases caused bycongenital metabolic disorders. More specifically, the present inventionrelates to the use of osteopontin, or of an agonist of osteopontinactivity, for the manufacture of a medicament for treatment and/orprevention of a neurologic disease.

BACKGROUND OF THE INVENTION

Nerve myelination is an essential process in the formation and functionof the central nervous system (CNS) and peripheral nervous system (PNS)compartments. The myelin sheath around axons is necessary for the properconduction of electric impulses along nerves. Loss of myelin occurs in anumber of diseases, among which are Multiple Sclerosis (MS) affectingthe CNS, Guillain-Barre Syndrome, CIDP and others (see Abramsky andOvadia, 1997; Trojaborg, 1998,Hartung et al, 1998). While of variousetiologies, such as infectious pathogens or autoimmune attacks,demyelinating diseases all cause loss of neurologic function and maylead to paralysis and death. While present therapeutical agents reduceinflammatory attacks in MS and retards disease progression, there is aneed to develop therapies that could lead to remyelination and recoveryof neurologic function (Abramsky and Ovadia, 1997, Pohlau et al, 1998).

Injury to CNS induced by acute insults including trauma, hypoxia andischemia can affect both neurons and white matter. Although mostattention has been paid to processes leading to neuronal death,increasing evidence suggests that damage to oligodendrocytes, whichmyelinate axons, is also a specific component of CNS injury. Thusoligodendrocyte pathology was demonstrated at very early phaseafter-stroke (3 hours) in rats, suggesting that these cells are evenmore vulnerable to excitotoxic events than neuronal cells (Pantoni etal. 1996). One potential candidate mediating cell death is the markedelevation of glutamate concentration that accompanies many acute CNSinjuries (Lipton et al. 1994). Indeed, beside neurons oligodendrocyteswere also found to express functional glutamate receptors belonging tothe AMPA/kainate subtype. Moreover oligodendrocytes display highvulnerability to glutamate application (McDonald et al. 1998).

Trauma is an injury or damage of the nerve. It may be spinal cordtrauma, which is damage to the spinal cord that affects all nervousfunction that is controlled at and below the level of the injury,including muscle control and sensation, or brain trauma, such as traumacaused by closed head injury.

Cerebral hypoxia is a lack of oxygen specifically to the cerebralhemispheres, and more typically the term is used to refer to a lack ofoxygen to the entire brain. Depending on the severity of the hypoxia,symptoms may range from confusion to irreversible brain damage, coma anddeath.

Stroke is usually caused by ischemia of the brain. It is also calledcerebrovascular disease or accident. It is a group of brain disordersinvolving loss of brain functions that occur when the blood supply toany part of the brain is interrupted. The brain requires about 20% ofthe circulation of blood in the body. The primary blood supply to thebrain is through 2 arteries in the neck (the carotid arteries), whichthen branch off within the brain to multiple arteries that each supply aspecific area of the brain. Even a brief interruption to the blood flowcan cause decreases in brain function (neurologic deficit). The symptomsvary with the area of the brain affected and commonly include suchproblems as changes in vision, speech changes, decreased movement orsensation in a part of the body, or changes in the level ofconsciousness. If the blood flow is decreased for longer than a fewseconds, brain cells in the area are destroyed (infarcted) causingpermanent damage to that area of the brain or even death.

A stroke affects about 4 out of 1,000 people. It is the 3rd leadingcause of death in most developed countries, including the U.S. Theincidence of stroke rises dramatically with age, with the risk doublingwith each decade after age 35. About 5% of people over age 65 have hadat least one stroke. The disorder occurs in men more often than women.

As mentioned above, a stroke involves loss of brain functions(neurologic deficits) caused by a loss of blood circulation to areas ofthe brain. The specific neurologic deficits may vary depending on thelocation, extent of the damage, and cause of the disorder. A stroke maybe caused by reduced blood flow (ischemia) that results in deficientblood supply and death of tissues in that area (infarction). Causes ofischemic strokes are blood clots that form in the brain (thrombus) andblood clots or pieces of atherosclerotic plaque or other material thattravel to the brain from another location (emboli). Bleeding(hemorrhage) within the brain may cause symptoms that mimic stroke.

The most common cause of a stroke is stroke secondary to atherosclerosis(cerebral thrombosis). Atherosclerosis (“hardening of the arteries”) isa condition in which fatty deposits occur on the inner lining of thearteries, and atherosclerotic plaque (a mass consisting of fattydeposits and blood platelets) develops. The occlusion of the arterydevelops slowly. Atherosclerotic plaque does not necessarily cause astroke. There are many small connections between the various brainarteries. If the blood flow gradually decreases, these small connectionswill increase in size and “by-pass” the obstructed area (collateralcirculation). If there is enough collateral circulation, even a totallyblocked artery may not cause neurologic deficits. A second safetymechanism within the brain is that the arteries are large enough that75% of the blood vessel can be occluded, and there will still beadequate blood flow to that area of the brain.

A thrombotic stroke (stroke caused by thrombosis) is most common inelderly people, and often there is underlying atherosclerotic heartdisease or diabetes mellitus. This type of stroke may occur at any time,including at rest. The person may or may not lose consciousness.

Strokes caused by embolism (moving blood clot) are most commonly strokessecondary to a cardiogenic embolism, clots that develop because of heartdisorders that then travel to the brain. An embolism may also originatein other areas, especially where there is atherosclerotic plaque. Theembolus travels through the bloodstream and becomes stuck in a smallartery in the brain. This stroke occurs suddenly with immediate maximumneurologic deficit. It is not associated with activity levels and canoccur at any time. Arrhythmias of the heart are commonly seen with thisdisorder and often are the cause of the embolus. Damage to the brain isoften more severe than with a stroke caused by cerebral thrombosis.Consciousness may or may not be lost. The probable outcome is worsenedif blood vessels damaged by stroke rupture and bleed (hemorrhagicstroke).

Peripheral Neuropathy is a syndrome of sensory loss, muscle weakness andatrophy, decreased deep tendon reflexes, and vasomotor symptoms, aloneor in any combination.

The disease may affect a single nerve (mononeuropathy), two or morenerves in separate areas (multiple mononeuropathy), or many nervessimultaneously (polyneuropathy). The axon may be primarily affected(e.g. in diabetes mellitus, Lyme disease, or uremia or with toxicagents) or the myelin sheath or Schwann cell (e.g. in acute or chronicinflammatory polyneuropathy, leukodystrophies, or Guillain-Barrésyndrome). Damage to small unmyelinated and myelinated fibers resultsprimarily in loss of temperature and pain sensation; damage to largemyelinated fibers results in motor or proprioceptive defects. Someneuropathies (e.g. due to lead toxicity, dapsone use, tick bite,porphyria, or Guillain-Barré syndrome) primarily affect motor fibers;others (e.g. due to dorsal root ganglionitis of cancer, leprosy, AIDS,diabetes mellitus, or chronic pyridoxine intoxication) primarily affectthe dorsal root ganglia or sensory fibers, producing sensory symptoms.Occasionally, cranial nerves are also involved (e.g. in Guillain-Barrésyndrome, Lyme disease, diabetes mellitus, and diphtheria). Identifyingthe modalities involved helps determine the cause.

Trauma is the most common cause of a localized injury to a single nerve.Violent muscular activity or forcible overextension of a joint mayproduce a focal neuropathy, as may repeated small traumas (e.g. tightgripping of small tools, excessive vibration from air hammers). Pressureor entrapment paralysis usually affects superficial nerves (ulnar,radial, peroneal) at bony prominences (e.g. during sound sleep or duringanesthesia in thin or cachectic persons and often in alcoholics) or atnarrow canals (e.g. in carpal tunnel syndrome). Pressure paralysis mayalso result from tumors, bony hyperostosis, casts, crutches, orprolonged cramped postures (e.g. in gardening). Hemorrhage into a nerveand exposure to cold or radiation may cause neuropathy. Mononeuropathymay result from direct tumor invasion.

Multiple mononeuropathy is usually secondary to collagen vasculardisorders (e.g. polyarteritis nodosa, SLE, Sjögren's syndrome, RA),sarcoidosis, metabolic diseases (e.g. diabetes, amyloidosis), orinfectious diseases (e.g. Lyme disease, HIV infection). Microorganismsmay cause multiple mononeuropathy by direct invasion of the nerve (e.g.in leprosy).

Polyneuropathy due to acute febrile diseases may result from a toxin(e.g. in diphtheria) or an autoimmune reaction (e.g. in Guillain-Barrésyndrome); the polyneuropathy that sometimes follows immunizations isprobably also autoimmune.

Toxic agents generally cause polyneuropathy but sometimesmononeuropathy. They include emetine, hexobarbital, barbital,chlorobutanol, sulfonamides, phenytoin, nitrofurantoin, the vincaalkaloids, heavy metals, carbon monoxide, triorthocresyl phosphate,orthodinitrophenol, many solvents, other industrial poisons, and certainAIDS drugs (e.g. zalcitabine, didanosine).

Nutritional deficiencies and metabolic disorders may result inpolyneuropathy. B vitamin deficiency is often the cause (e.g. inalcoholism, beriberi, pernicious anemia, isoniazid-induced pyridoxinedeficiency, malabsorption syndromes, and hyperemesis gravidarum).Polyneuropathy also occurs in hypothyroidism, porphyria, sarcoidosis,amyloidosis, and uremia. Diabetes mellitus can cause sensorimotor distalpolyneuropathy (most common), multiple mononeuropathy, and focalmononeuropathy (e.g. of the oculorrotor or abducens cranial nerves).

Malignancy may cause polyneuropathy via monoclonal gammopathy (multiplemyeloma, lymphoma), amyloid invasion, or nutritional deficiencies or asa paraneoplastic syndrome.

Specific mononeuropathies: Single and multiple mononeuropathies arecharacterized by pain, weakness, and paresthesias in the distribution ofthe affected nerve. Multiple mononeuropathy is asymmetric; the nervesmay be involved all at once or progressively. Extensive involvement ofmany nerves may simulate a polyneuropathy.

Ulnar nerve palsy is often caused by trauma to the nerve in the ulnargroove of the elbow by repeated leaning on the elbow or by asymmetricbone growth after a childhood fracture (tardy ulnar palsy). The ulnarnerve can also be compressed at the cubital tunnel. Paresthesias and asensory deficit in the 5th and medial half of the 4th fingers occur; thethumb adductor, 5th finger abductor, and interossei muscles are weak andatrophied. Severe chronic ulnar palsy produces a clawhand deformity.Nerve conduction studies can identify the site of the lesion.Conservative treatment should be attempted before surgical repair isattempted.

The carpal tunnel syndrome results from compression of the median nervein the volar aspect of the wrist between the transverse superficialcarpal ligament and the longitudinal tendons of forearm muscles thatflex the hand. It may be unilateral or bilateral. The compressionproduces paresthesias in the radial-palmar aspect of the hand and painin the wrist and palm; sometimes pain occurs proximally to thecompression site in the forearm and shoulder. Pain may be more severe atnight. A sensory deficit in the palmar aspect of the first three fingersmay follow; the muscles that control thumb abduction and opposition maybecome weak and atrophied. This syndrome should be distinguished fromC-6 root compression due to cervical radiculopathy.

Peroneal nerve palsy is usually caused by compression of the nerveagainst the lateral aspect of the fibular neck. It is most common inemaciated bedridden patients and in thin persons who habitually crosstheir legs. Weakness of foot dorsiflexion and eversion (footdrop) occur.Occasionally, a sensory deficit occurs over the anterolateral aspect ofthe lower leg and dorsum of the foot or in the web space between the 1stand 2nd metatarsals. Treatment is usually conservative for compressiveneuropathies (e.g. avoiding leg crossing). Incomplete neuropathies areusually followed clinically and usually improve spontaneously. Ifrecovery does not occur, surgical exploration may be indicated.

Radial nerve palsy (Saturday night palsy) is caused by compression ofthe nerve against the humerus, e.g. as the arm is draped over the backof a chair during intoxication or deep sleep. Symptoms include weaknessof wrist and finger extensors (wristdrop) and, occasionally, sensoryloss over the dorsal aspect of the 1st dorsal interosseous muscle.Treatment is similar to that of compressive peroneal neuropathy.

Polyneuropathies are relatively symmetric, often affecting sensory,motor, and vasomotor fibers simultaneously. They may affect the axoncylinder or the myelin sheath and, in either form, may be acute (e.g.Guillain-Barré syndrome) or chronic (e.g. renal failure).

Polyneuropathy due to metabolic disorders (e.g. diabetes mellitus) orrenal failure develops slowly, often over months or years. It frequentlybegins with sensory abnormalities in the lower extremities that areoften more severe distally than proximally. Peripheral tingling,numbness, burning pain, or deficiencies in joint proprioception andvibratory sensation are often prominent. Pain is often worse at nightand may be aggravated by touching the affected area or by temperaturechanges. In severe cases, there are objective signs of sensory loss,typically with stocking-and-glove distribution. Achilles and other deeptendon reflexes are diminished or absent. Painless ulcers on the digitsor Charcot's joints may develop when sensory loss is profound. Sensoryor proprioceptive deficits may lead to gait abnormalities. Motorinvolvement results in distal muscle weakness and atrophy. The autonomicnervous system may be additionally or selectively involved, leading tonocturnal diarrhea, urinary and fecal incontinence, impotence, orpostural hypotension. Vasomotor symptoms vary. The skin may be paler anddrier than normal, sometimes with dusky discoloration; sweating may beexcessive. Trophic changes (smooth and shiny skin, pitted or ridgednails, osteoporosis) are common in severe, prolonged cases.

Nutritional polyneuropathy is common among alcoholics and themalnourished. A primary axonopathy may lead to secondary demyelinationand axonal destruction in the longest and largest nerves. Whether thecause is deficiency of thiamine or another vitamin (e.g. pyridoxine,pantothenic acid, folic acid) is unclear. Neuropathy due to pyridoxinedeficiency usually occurs only in persons taking isoniazid for TB;infants who are deficient or dependent on pyridoxine may haveconvulsions. Wasting and symmetric weakness of the distal extremities isusually insidious but can progress rapidly, sometimes accompanied bysensory loss, paresthesias, and pain. Aching, cramping, coldness,burning, and numbness in the calves and feet may be worsened by touch.Multiple vitamins may be given when etiology is obscure, but they haveno proven benefit.

Uncommonly, an exclusively sensory polyneuropathy begins with peripheralpains and paresthesias and progresses centrally to a loss of all formsof sensation. It occurs as a remote effect of carcinoma (especiallybronchogenic), after excessive pyridoxine ingestion (>0.5 g/day), and inamyloidosis, hypothyroidism, myeloma, and uremia. The pyridoxine-inducedneuropathy resolves when pyridoxine is discontinued.

Hereditary neuropathies are classified as sensorimotor neuropathies orsensory neuropathies. Charcot-Marie-Tooth disease is the most commonhereditary sensorimotor neuropathy. Less common sensorimotorneuropathies begin at birth and result in greater disability. In sensoryneuropathies, which are rare, loss of distal pain and temperaturesensation is more prominent than loss of vibratory and position sense.The main problem is pedal mutilation due to pain insensitivity, withfrequent infections and osteomyelitis.

Hereditary motor and sensory neuropathy types I and II(Charcot-Marie-Tooth disease, peroneal muscular atrophy) is a relativelycommon, usually autosomal dominant disorder characterized by weaknessand atrophy, primarily in peroneal and distal leg muscles. Patients mayalso have other degenerative diseases (e.g. Friedreich's ataxia) or afamily history of them. Patients with type I present in middle childhoodwith footdrop and slowly progressive distal muscle atrophy, producing“stork legs.” Intrinsic muscle wasting in the hands begins later.Vibration, pain, and temperature sensation decreases in a stocking-glovepattern. Deep tendon reflexes are absent. High pedal arches or hammertoes may be the only signs in less affected family members who carry thedisease. Nerve conduction velocities are slow, and distal latenciesprolonged. Segmental demyelination and remyelination occur. Enlargedperipheral nerves may be palpated. The disease progresses slowly anddoes not affect life span. Type II disease evolves more slowly, withweakness usually developing later in life. Patients have relativelynormal nerve conduction velocities but low amplitude evoked potentials.Biopsies show wallerian degeneration.

Hereditary motor and sensory neuropathy type III (hypertrophicinterstitial neuropathy, Dejerine-Sottas disease), a rare autosomalrecessive disorder, begins in childhood with progressive weakness andsensory loss and absent deep tendon reflexes. Initially, it resemblesCharcot-Marie-Tooth disease, but motor weakness progresses at a fasterrate. Demyelination and remyelination occur, producing enlargedperipheral nerves and onion bulbs seen on nerve biopsy.

The characteristic distribution of motor weakness, foot deformities,family history, and electrophysiologic abnormalities confirm thediagnosis. Genetic analysis is available, but no specific treatment.Vocational counseling to prepare young patients for disease progressionmay be useful. Bracing helps correct footdrop; orthopedic surgery tostabilize the foot may help.

Neurodegenerative diseases comprise, among others, Alzheimer's disease,Parkinson's disease, Huntington's disease and Amyotrophic LateralSclerosis (ALS).

Alzheimer's disease is a disorder involving deterioration in mentalfunctions resulting from changes in brain tissue. This includesshrinking of brain tissues, not caused by disorders of the bloodvessels, primary degenerative dementia and diffuse brain atrophy.Alzheimer's disease is also called senile dementia/Alzheimer's type(SDAT). It is the most common cause of intellectual decline with aging.The incidence is approximately 9 out of 10,000 people. This disorderaffects women slightly more often than men and occurs primarily in olderindividuals.

The cause is unknown. The neurochemical factors which may participate ingeneration of the disease include lack of the substances used by thenerve cells to transmit nerve impulses (neurotransmitters), includingacetylcholine, somatostatin, substance P, and norepinephrine.Environmental factors include exposure to aluminum, manganese, and othersubstances. The infectious factors include prion (virus-like organisms)infections that affect the brain and spinal cord (central nervoussystem). In some families (representing 5 to 10% of cases) there is aninherited predisposition to development of the disorder, but this doesnot follow strict (Mendelian) patterns of inheritance. The diagnosis isusually made by ruling out other causes of dementia.

Researchers have found that in families that have multiple members withAlzheimer's, there is a particular gene variation which is common to allof those with the disease. The gene, which produces a substance calledapolipoprotein E4, is not said to cause the disease, it's presencesimply increases the chances that the disease may eventually occur.There are many people who have the E4 gene and never become afflictedwith Alzheimer's.

The onset is characterized by impaired memory, with progressive loss ofintellectual function. There may be mood changes, changes in languagecapability, changes in gait, and other changes as the disorderprogresses. There is a decrease in the size (atrophy) of the tissues ofthe brain, enlargement of the ventricles (the spaces within the brain),and deposits within the tissues of the brain.

Parkinsons's disease is a disorder of the brain characterized by shakingand difficulty with walking, movement, and coordination. The disease isassociated with damage to a part of the brain that controls musclemovement. It is also called paralysis agitans or shaking palsy.

The disease affects approximately 2 out of 1,000 people, and most oftendevelops after age 50. It affects both men and women and is one of themost common neurologic disorders of the elderly. The term “parkinsonism”refers to any condition that involves a combination of the types ofchanges in movement seen in Parkinson's disease, which happens to be themost common condition causing this group of symptoms. Parkinsonism maybe caused by other disorders or by external factors (secondaryparkinsonism).

Parkinson's disease is caused by progressive deterioration of the nervecells of the part of the brain that controls muscle movement (the basalganglia and the extrapyramidal area). Dopamine, which is one of thesubstances used by cells to transmit impulses (transmitters), isnormally produced in this area. Deterioration of this area of the brainreduces the amount of dopamine available to the body. Insufficientdopamine disturbs the balance between dopamine and other transmitters,such as acetylcholine. Without dopamine, the nerve cells cannot properlytransmit messages, and this results in the loss of muscle function. Theexact reason that the cells of the brain deteriorate is unknown. Thedisorder may affect one or both sides of the body, with varying degreesof loss of function.

In addition to the loss of muscle control, some people with Parkinson'sdisease become severely depressed. Although early loss of mentalcapacities is uncommon, with severe Parkinson's the person may exhibitoverall mental deterioration (including dementia, hallucinations, and soon). Dementia can also be a side effect of some of the medications usedto treat the disorder.

Huntington's Disease is an inherited, autosomal dominant neurologicdisease. It is uncommon, affecting approximately 1 in 10000 individuals(Breighton and Hayden 1981). The disease does not usually becomeclinically apparent until the fifth decade of life, and results inpsychiatric disturbance, involuntary movement disorder, and cognitivedecline associated with inexorable progression to death, typically 17years following onset.

The gene responsible for Huntington's disease is called huntingtin. Itis located on chromosome 4p, presenting an effective means ofpreclinical and antenatal diagnosis. The genetic abnormality consists inan excess number of tandemly repeated CAG nucleotide sequences.

The increase in size of the CAG repeat in persons with Huntington'sdisease shows a highly significant correlation with age of onset ofclinical features. This association is particularly striking for personswith juvenile onset Huntington's disease who have very significantexpansion, usually beyond 50 repeats. The CAG repeat length inHuntington's disease families does exhibit some instability that isparticularly marked when children inherit the huntingtin gene fromaffected fathers.

In HD, it is not known how this widely, expressed gene, results inselective neuronal death. Further, sequence analysis revealed no obvioushomology to other known genes and no structural motifs or functionaldomains were identified which clearly provide insights into itsfunction. In particular, the question of how these widely expressedgenes cause selective neuronal death remains unanswered.

Amyptrophic Lateral Sclerosis, ALS, is a disorder causing progressiveloss of nervous control of voluntary muscles because of destruction ofnerve cells in the brain and spinal cord. Amyotrophic Lateral Sclerosis,also called Lou Gehrig's disease, is a disorder involving loss of theuse and control of muscles. The nerves controlling these muscles shrinkand disappear, which results in loss of muscle tissue due to the lack ofnervous stimulation. Muscle strength and coordination decreases,beginning with the voluntary muscles (those under conscious control,such as the muscles of the arms and legs). The extent of loss of musclecontrol continues to progress, and more and more muscle groups becomeinvolved. There may be a loss of nervous stimulation to semi-voluntarymuscles, such as the muscles that control breathing and swallowing.There is no effect on ability to think or reason. The cause is unknown.

ALS affects approximately 1 out of 100,000 people. It appears in somecases to run in families. The disorder affects men more often thanwomen. Symptoms usually do not develop until adulthood, often not untilafter age 50.

Traumatic nerve injury may concern the CNS or the PNS. Traumatic braininjury (TBI), also simply called head injury or closed head injury(CHI), refers to an injury where there is damage to the brain because ofan external blow to the head. It mostly happens during car or bicycleaccidents, but may also occur as the result of near drowning, heartattack, stroke and infections. This type of traumatic brain injury wouldusually result due to the lack of oxygen or blood supply to the brain,and therefore can be referred to as an “anoxic injury”.

Brain injury or closed head injury occurs when there is a blow to thehead as in a motor vehicle accident or a fall. In this case, the skullhits a stationary object and the brain, which is inside the skull, turnsand twists on its axis (the brain stem), causing localised or widespreaddamage. Also, the brain, a soft mass surrounded by fluid that allows itto “float,” may rebound against the skull resulting in further damage.

There may be a period of unconsciousness immediately following thetrauma, which may last minutes, weeks or months. Due to the twisting andrebounding, the traumatically brain injured patient usually receivesdamage or bruising to many parts of the brain. This is called diffusedamage, or “non-missile injury” to the brain. The types of brain damagesoccurring in non-missile injuries may be classified as either primary orsecondary.

Primary brain damage occurs at the time of injury, mainly at the sitesof impact, in particular when a skull fraction is present. Largecontusions may be associated with an intracerebral hemorrhage, oraccompanied by cortical lacerations. Diffuse axonal injuries occur as aresult of shearing and tensile strains of neuronal processes produced byrotational movements of the brain within the skull. There may be smallhemorrhagic lesions or diffuse damage to axons, which can only bedetected microscopically.

Secondary brain damage occurs as a result of complications developingafter the moment of injury. They include intracranial hemorrhage,traumatic damage to extracerebral arteries, intracranial herniation,hypoxic brain damage or meningitis.

An open head injury is a visible assault to the head and may result froma gunshot wound, an accident or an object going through the skull intothe brain (“missile injury to the brain”). This type of head injury ismore likely to damage a specific area of the brain.

So called mild brain injury may occur with no loss of consciousness andpossibly only a dazed feeling or confused state lasting a short time.Although medical care administered may be minimal, persons with braininjury without coma may experience symptoms and impairments similar tothose suffered by the survivor of a coma injury.

In response to the trauma, changes occur in the brain which requiremonitoring to prevent further damage. The brain's size frequentlyincreases after a severe head injury. This is called brain swelling andoccurs when there is an increase in the amount of blood to the brain.Later in the illness water may collect in the brain which is calledbrain edema. Both brain swelling and brain edema result in excessivepressure in the brain called intracranial pressure (“ICP”).

Spinal cord injuries account for the majority of hospital admissions forparaplegia and tetraplegia. Over 80% occur as a result of roadaccidents. Two main groups of injury are recognised clinically: openinjuries and closed injuries.

Open injuries cause direct trauma of the spinal cord and nerve roots.Perforating injuries can cause extensive disruption and hemorrhage.Closed injuries account for most spinal injuries and are usuallyassociated with a fracture/dislocation of the spinal column, which isusually demonstrable radiologically. Damage to the cord depends on theextent of the bony injuries and can be considered in two main stages:Primary damage, which are contusions, nerve fibre transections andhemorrhagic necrosis, and secondary damage, which are extraduralheamatoma, infarction, infection and edema.

Late effects of cord damage include: ascending and descendinganterograde degeneration of damaged nerve fibers, post-traumaticsyringomelyia, and systemic effects of paraplegia, such as urinary tractand chest infections, pressure sores and muscle wasting.

Neurologic disorders may further be due to congenital metabolicdisorders. Myelin sheaths, which cover many nerve fibers, are composedof lipoprotein layers formed in early life. Myelin formed by theoligodendroglia in the CNS differs chemically and immunologically fromthat formed by the Schwann cells peripherally, but both types have thesame function: to promote transmission of a neural impulse along anaxon.

Many congenital metabolic disorders (e.g. phenylketonuria and otheraminoacidurias; Tay-Sachs, Niemann-Pick, and Gaucher's diseases;Hurler's syndrome; Krabbe's disease and other leukodystrophies) affectthe developing myelin sheath, mainly in the CNS. Unless the biochemicaldefect can be corrected or compensated for, permanent, often widespread,neurologic deficits result.

For instance, Krabbe disease or globoid cell leukodystrophy is adisorder involving the white matter of the peripheral and centralnervous systems. Mutations in the gene for the lysosomal enzymegalactocerebrosidase (GALC) result in low enzymatic activity anddecreased ability to degrade galactolipids found almost exclusively inmyelin. Continued myelination and/or remyelination in patients requiresfunctional endogenous oligodendrocytes or transplantation of normaloligodendrocytes or stem cells that can differentiate intooligodendrocytes, in order to provide for sufficient GALC expression(Wenger et al., 2000).

Neurofibromatosis 1 (NF1) is a common autosomal disorder with a widerange of neurologic manifestations.

Multiple system atrophy is a sporadic, adult-onset neurodegenerativedisease of unknown etiology. The condition may be unique amongneurodegenerative diseases by the prominent, if not primary, role playedby the oligodendroglial cell in the pathogenetic process. The majordifference to Parkinson's disease is that MSA patients do not respond toL-dopa treatment.

Demyelination in later life is a feature of many neurologic disorders;it can result from damage to nerves or myelin due to local injury,ischemia, toxic agents, or metabolic disorders. There is also evidencethat demyelination may contribute to schizophrenia. Extensive myelinloss is usually followed by axonal degeneration and often by cell bodydegeneration, both of which may be irreversible. However, remyelinationoccurs in many instances, and repair, regeneration, and complete,recovery of neural function can be rapid. Central demyelination (ie, ofthe spinal cord, brain, or optic nerves) is the predominant finding inthe primary demyelinating diseases, whose etiology is unknown. The mostwell known is MS.

Acute disseminated encephalomyelitis, postinfectious encephalomyelitisis characterized by perivascular CNS demyelination, which can occurspontaneously but usually follows a viral infection or viral vaccination(or, very rarely, bacterial vaccination), suggesting an immunologiccause. Acute inflammatory peripheral neuropathies that follow a viralvaccination or the Guillain-Barré syndrome are similar demyelinatingdisorders with the same presumed immunopathogenesis, but they affectonly peripheral structures.

Metachromatic leukodystrophy is another demyelinating disease.Adrenoleukodystrophy and adrenomyeloneuropathy are rare X-linkedrecessive metabolic disorders characterized by adrenal gland dysfunctionand widespread demyelination of the nervous system. Adrenoleukodystrophyoccurs in young boys; adrenomyeloneuropathy, in adolescents. Mentaldeterioration, spasticity, and blindness may occur. Adrenoleukodystrophyis invariably fatal. Dietary and immunomodulatory treatments are understudy.

Leber's hereditary optic atrophy and related mitochondrial disorders arecharacterized primarily by bilateral loss of central vision, usuallyaffecting young men in their late teens or early twenties. Leber'shereditary optic atrophy can resemble the optic neuritis in MS.Mutations in the maternally inherited mitochondrial DNA have beenidentified.

HTLV-associated myelopathy, a slowly progressive spinal cord diseaseassociated with infection by the human T-cell lymphotrophic virus, ischaracterized by spastic weakness of both legs.

Further neurologic disorders comprise neuropathies with abnormalmyelination, an overview of which is given below.

Immune: Acute, Guillain Barré, Chronic, Chronic Immune DemyelinatingPolyneuropathy (CIDP), Multifocal CIDP, Multifocal Motor Neuropathy(MMN), Anti-MAG Syndrome, GALOP Syndrome, Anti-Sulfatide AntibodySyndrome (with serum M-protein), Anti-GM2 antibody syndrome, POEMSSyndrome, Polyneuropathy Organomegaly, Endocrinopathy or Edema,M-protein, Skin changes, Perineuritis, IgM anti-GD1b antibody syndrome(occasional).

Toxins: Diphtheria, Buckthorn, Hexachlorophene, Sodium Cyanate,Tellurium.

Drugs: Predominantly demyelinating: Chloroquine, FK506 (Tacrolimus),Perhexiline, Procainamide, Zimeldine; Mixed demyelinating & axonal:Amiodarone, Eosinophilia-Myalgia syndrome, Gold, Suramin, Taxol.

Hereditary: Carbohydrate-deficient glycoprotein, Cataracts & Facialdysmorphism, Cockayne's syndrome, Congenital hypomyelinating, Congenitalmuscular dystrophy: Merosin deficient, Farber's disease(Lipogranulomatosis), HMSN & CMT, Dominant: IA, IB, III, HNPP, EGR2,Thermosensitive, Recessive: III (Dejerine-Sottas); 4A; 4B; 4B2; 4C; 4D(LOM); 4E; 4F; HMSN-R; CNS, X-linked: IX, Krabbe, Marinesco-Sjögren,Metachromatic Leukodystrophy, Niemann-Pick, Pelizaeus-Merzbacher (PLP),Refsum, Prion protein (PrP27-30): Glu200Lys mutation, Creutzfeld-Jakobdisease, Mouse model: Prion over expression, Salla disease, SOX10,Tenascin-XA, Uneven packing of peripheral myelin sheaths, Ehlers-Danlosphenotype.

Metabolic (unusual): Diabetes (due to concurrent CIDP), Hypothyroidism,Hepatic disorders.

Mitochondrial: MNGIE Syndrome, Myopathy & external ophthalmoplegia,neuropathy, Gastro-Intestinal Encephalopathy, NARP Syndrome, Neuropathy,Ataxia, Retinitis, Pigmentosa.

Infections: Creutzfeld-Jakob disease, Diphtheria, HIV: Associated CIDP,Leprosy: Lepromatous; Mixed axonal-demyelinating; Colonized Schwancells, Variant Creutzfeld-Jakob disease.

Further details can be taken from the following internet-site:www.neuro.wustl.edu/neuromuscular/nother/myelin.html.

Multiple Sclerosis (MS) is an inflammatory demyelinating disease of thecentral nervous system (CNS) that takes a relapsing-remitting or aprogressive course. MS is not the only demyelinating disease. Itscounterpart in the peripheral nervous system (PNS) is chronicinflammatory demyelinating polyradiculoneuropathy (CIDP). In addition,there are acute, monophasic disorders, such as the inflammatorydemyelinating polyradiculoneuropathy termed Guillain-Barré syndrome(GBS) in the PNS, and acute disseminated encephalomyelitis (ADEM) in theCNS. Both MS and GBS are heterogeneous syndromes. In MS differentexogenous assaults together with genetic factors can result in a diseasecourse that finally fulfils the diagnostic criteria. In both diseases,axonal damage can add to a primarily demyelinating lesion and causepermanent neurologic deficits.

MS is the most common of the above demyelinating diseases. It ischaracterized as an autoimmune disorder, in which leukocytes of theimmune system launch an attack on the white matter of the centralnervous system (CNS). The grey matter may also be involved. Although theprecise etiology of MS is not known, contributing factors may includegenetic, bacterial and viral infection. In its classic manifestation(85% of all cases), it is characterized by alternatingrelapsing/remitting phases, which correspond to episodes of neurologicdysfunction lasting several weeks followed by substantial or completerecovery (Noseworthy, 1999). Periods of remission grow shorter overtime. Many patients then enter a final disease phase characterized bygradual loss of neurologic function with partial or no recovery. This istermed secondary progressive MS. A small proportion (˜15% of all MSpatients) suffers a gradual and uninterrupted decline in neurologicfunction following onset of the disease (primary progressive MS). Thereis currently no clear curative treatment for the severest forms of MS,which are generally fatal.

The basic hallmark of MS is the demyelinated plaque with reactive glialscar formation, seen in the white matter tracts of the brain and spinalcord. Demyelination is linked to functional reduction or blockage inneural impulse conduction. Axonal transection and death is also observedin MS patients (Bjartmar et al., 1999). Pathological studies show themajority of involvement limited to the optic nerves, periventricularwhite matter, brain stem and spinal cord (Storch et al., 1998). Theeffects of these CNS deficiencies include the acute symptoms ofdiplopia, numbness and unsteady gait, as well as chronic symptoms suchas spastic paraparesis and incontinence.

Molecular mechanisms underlying MS pathogenesis appear to stem fromgenetic and environmental factors, including viral and bacterialinfections. These mechanisms promote increased migration of Tlymphocytes and macrophages across the blood-brain barrier and into CNStissue.

Demyelination is caused by attacks on myelin by activated macrophagesand microglia, as well as damage to myelinating cells stemming fromFas-ligand signaling and complement- or antibody-mediated cytotoxicity.Therefore, demyelination occurs through both a direct attack on themyelin sheaths as well as elimination of the cells that produce andmaintain myelin.

Genetic and environmental elements lead to an increased influx ofinflammatory cells across the blood-brain barrier. This results in theincreased migration of autoreactive T lymphocytes and macrophages intoCNS tissue. Cytokine secretion by T cells activates antigen-presentingcells (APCs). When autoreactive T cells in the context of MHC class IImolecules on APCs encounter putative ‘MS antigens’, often proteinconstituents of the myelin sheath, they may become activated. Severalsubsequent mechanisms can then act to damage oligodendrocytes andmyelin. Complement- and antibody-mediated cytotoxicity may cause themajority of damage in some patients, while Fas-ligand signaling, andrelease of pro-inflammatory cytokines like TNF-α by CD4+ T cells mayattack white matter in others. Activated macrophages may also play arole through enhanced phagocytosis and factor secretion. This causeswidespread demyelination and, subsequent loss of conduction efficiencyamong the axons of the CNS. Subsequent repair mechanisms can, however,give rise to remyelination once the inflammatory process is resolved.The remyelinated axons of MS patients are recognized pathologically bythe thin appearance of the sheaths around the remyelinated axons.Additional sodium channels are often found inserted into thedemyelinated axonal membrane, compensating for the loss of conductionefficiency. Oligodendroglial precursors may enhance remyelination in MSlesions.

The oligodendrocyte performs a multitude of functions related to itsproduction and maintenance of the myelin sheath. This providesinsulation, support and conductance enhancement for the axons ofmultiple neurons. A single oligodendrocyte may myelinate up to 50different axons. Myelination is restricted only to certain, largediameter axons; dendrites and other cell processes, such as those ofastrocytes, remain unmyelinated. Axons appear to exert control over thenumber of myelinating oligodendrocytes, since axonal transection in theparadigm of the rat optic nerve inhibits myelin renewal andoligodendrocyte precursor production (reviewed in Barres and Raff,1999). Oligodendrocyte proliferation and migration may be stimulated byfactors released from axons during development. In this manner, thenumbers of oligodendrocytes and axons are carefully matched within theCNS.

Oligodendrocytes, the perineuronal support cells of the CNS, myelinateaxonal tracts and serve to enhance impulse transduction. They play rolesin axonal survival and function. Note that, as shown in this diagram, anoligodendrocyte extends only one process to each axon it myelinates.

The multilamellar myelin sheath is a specialized domain of the glialcell plasma membrane, rich in lipid and low in protein. It serves tosupport axons and improve the efficiency of electrical signal conductionin the CNS by preventing the charge from bleeding off into thesurrounding tissue. The nodes of Ranvier are the sites in the sheathalong the axon where saltatory conductance occurs.

In the adult brain, oligodendrocytes develop from as yet poorly definedprecursor cells in the subventricular zone of the brain and spinal cord(Nait-Oumesmar et al., 1999). These precursors are proliferative andexpress myelin transcripts and proteins, first emerging in the ventralregion of the embryonic spinal cord several weeks before myelination(Hajihosseini et al., 1996). The process of myelination occurs in thepost-natal brain. During post-natal development, these precursorsmigrate to the neuron tracts that are to be myelinated.

Oligodendrocytes mature from their precursor cells in a defined andspecific manner (reviewed e.g. in Rogister et al., 1999).Oligodendrocyte development follows a defined pathway at which eachstage is demarcated by several cell-specific markers: endothelial neuralcell adhesion molecule (E-NCAM), vimentin, A2B5, the POU transcriptionfactor Tst-1/Oct6/SCIP, pre-oligodendroblast antigen (POA),galactocerebroside (GalC), O1, O4, and the myelin-specific; proteinsPLP, MBP, and MOG. Neural stem cells give rise to bipolar pre-GD3⁺cells,which become O2A precursors. These cells can give rise to eitheroligodendrocytes or type 2 astrocytes. Progression continues through thepre-oligodendroglial and pre-GalC⁺stages, before actual differentiationinto oligodendrocytes. The end stages of the oligodendroglial lineageare defined by these cells' inability to proliferate. Matureoligodendrocytes express the cell-specific markers GalC and sulfatide(SUL), in addition to expressing myelin-specific proteins.

Oligodendrocytes therefore differentiate from mitotically active,migratory precursor cells. Once these cells have become post-mitotic,they transcribe and translate genes encoding myelin-specific proteins.The elaboration of the myelin sheath wrapping the axon is brought aboutby direct contact between the processes of the mature oligodendrocyteand the axon itself. CNS axon ensheathment is completed by compaction ofthe myelin sheath, which in its final form resembles a liquid crystalcontaining macromolecules in complex formation (Scherer, 1997).Promotion of myelination; demands consideration of the precisestoichiometric relationship between the individual structural proteinsof the myelin sheath, since increasing or decreasing the amount of onecomponent could result in perturbation of the entire sheath structure.

The inability of oligodendrocytes to sustain repair of demyelinatedaxons contributes to the cumulative neurologic dysfunctioncharacterizing MS. Promotion of remyelination in MS patients couldprotect axonal loss and thus limit the progression in disabilityassociated with the death of axons in the CNS.

The demyelinating phenotype of MS led to extensive studies on the natureof the active MS lesion. Naked axons and the absence of myelinatingoligodendrocytes indicated the disruption of normal myelin andaberrations in the remyelinating process associated with MS. About 40%of MS lesions were shown to exhibit evidence of abortive remyelination,especially in the early phases of the disease (Prineas et al., 1993).This presents the realistic prospect that developing strategies forpromoting myelin repair could prevent permanent nervous system damage.Success probability is particularly high in younger CNS lesions, whereearly remyelination has already been shown to take place. However, themyelinating or remyelinating oligodendrocyte is a cell under extrememetabolic stress, which under pressure of even minor additional insultscan be irreversibly damaged (Scolding and Lassmann, 1996). Thisdecreases the probability of spontaneous repair in an active MS lesion,where inflammation and other detriments pose obstacles to remyelination.Strategies promoting myelin repair may thus stack the odds further infavor of remyelination and axonal protection in active MS lesions.

The adult human CNS has been shown to contain oligodendrocyte precursorcells that are capable of proliferating, and which could mature intomyelinating oligodendrocytes. In addition, it appears that theendogenous oligodendrocyte precursor populations adjacent to MS lesionsare depleted during the chronic phases of the disease, due to inhibitionof these precursors' ability to proliferate and differentiate (Wolswijk,1998). Such precursor cells are generally quiescent in the environmentof a chronic MS lesion, preventing them from actively contributing toremyelination. The situation in chronic MS lesions could thereforeinvolve factors that hamper oligodendroglial regeneration or lackfactors necessary for the stimulation of the oligodendrocyte precursorcell population (Wolswijk, 1998). This concept led to the hypothesisthat an efficient therapy for MS should not be limited to suppressinginflammation but should also favor remyelination. The remyelinatingcells could originate from a variety of sources, including survivingoligodendrocytes native to the lesion, cells derived from thesesurvivors, or the adjacent precursor cells. It has been shown thatmature oligodendrocytes can be induced to dedifferentiate andproliferate by factors such as basic fibroblast growth factor (bFGF),suggesting a mechanism for regeneration of the oligodendroglial lineagefollowing demyelinating disease (Grinspan et al., 1996; Grinspan et al.,1993).

Additional evidence for the beneficial effects of remyelination indemyelinating disorders such as MS is provided by the studies performedwith glial growth factors as treatments in animal models of the disease.Glial growth factor 2 (neuregulin/GGF-2), a CNS growth factor known topromote oligodendrocyte proliferation and survival, was shown to delaydisease onset, reduce clinical severity and decrease relapse frequencyin the EAE murine model of MS (Marchionni et al., 1999). Neuregulin wasshown to have a beneficial effect on mature oligodendrocyte survival andis produced by axons (Fernández et al., 2000).

Other growth factors, including platelet-derived growth factor (PDGF)and IGF-1, have been demonstrated to promote remyelination and havetherapeutic effects in EAE models (reviewed in Dubois-Dalcq and Murray,2000). The success achieved with the stimulation of remyelination,through inducing cells of the oligodendrocyte lineage to proliferateand/or differentiate, indicates that prospects for remyelination as atherapeutic strategy for MS are favorable. It would also be important toidentify molecules that inhibit myelin synthesis, since these couldlower the effectiveness of repair strategies such as oligodendroglialcell transplantation in MS.

The process of remyelination could work in concert withanti-inflammatory pathways to repair damage and protect axons fromtransection and death.

Oligodendrocytes may be induced to remyelinate axonal tracts in the CNS,thereby contributing to amelioration of the disease condition.Remyelination enhancement would counteract the previous destructionwrought by invasion of immune system cells into CNS tissue and theirattack on myelin sheaths.

Several analyses of oligodendroglial differentiation and multiplesclerosis lesions have been performed using microarray visualization ofdifferential gene expression (DGE, Scarlato et al., 2000; Whitney etal., 1999). These have utilized significantly different arraytechnologies to assay varying sets of genes. Analysis of gene expressionin both differentiating oligodendrocytes and multiple sclerosis lesionshave indicated significant changes in the expression of myelin-specificgenes. In addition, other genes were pinpointed as being differentiallyregulated, many of which were known to be involved in processes such ascell cycle control, cytoskeletal reorganization and membrane trafficking(Scarlato et al., 2000).

Osteopontin is a highly phosphorylated sialoprotein that is a prominentcomponent of the mineralized extracellular matrices of bones and teeth.OPN is characterized by the presence of a polyaspartic acid sequence andsites of Ser/Thr phosphorylation that mediate hydroxyapatite binding,and a highly conserved RGD motif that mediates cellattachment/signaling. Expression of osteopontin in a variety of tissuesindicates a multiplicity of functions that involve one or more of theseconserved motifs. While the lack of a clear phenotype in OPN “knockout”mice has not established, a definitive role for osteopontin in anyissue, recent studies have provided some novel and intriguing insightsinto the versatility of this protein in diverse biological events,including developmental processes, wound healing, immunologicalresponses, tumorigenesis, bone resorption, and calcification. Theability of osteopontin to stimulate cell activity through multiplereceptors linked to several interactive signaling pathways can accountfor much of the functional diversity (Sodek et al.).

Osteopontin has also been shown to be expressed in primary sensoryneurons in the rat spinal and trigeminal nervous systems, both in theneuronal cell bodies and in the axons (Ichikawa et al., 2000).

Osteopontin mRNA is expressed in the adult brain as shown by in situhybridization. Expression was found in neurons of the olfactory bulb andthe brain stem, and in the latter it was found in functionally diverseareas including motor-related areas, sensory system and reticularformation (Shin et al., 1999).

Another study investigated the spatial and temporal expression ofosteopontin mRNA following transient forebrain ischemia in rats. Thetransient induction of OPN mRNA after global ischemia occurred earlierin the striatum than in the hippocampus. It was pronounced in thedorsomedial striatum close to the lateral ventricle and in the CA1subfield and the subiculum of the hippocampus before microglial cellsbecame more reactive. It also could be detected in the dentate hilus,and to a marginal extent in the CA3 (Lee M Y, Shin S L, Choi Y S, Kim EJ, Cha J H, Chun M H, Lee S B, Kim S Y, Neurosci Lett Aug. 20, 1999271:2 81–4).

Osteopontin is also called Eta-1. WO 00/63241 relates to methods formodulating immune responses, in particular methods for modulating type 1immune responses using modulators of Eta-1 (early T lymphocyteactivation-1)/osteopontin. Osteopontin modulators are said to be usefulfor treatment of infections, immune disorders and diseases, autoimmunedisorders, including MS, various immunodeficiencies, and cancer. Allmodulators of osteopontin disclosed in WO 00/63241, which are envisagedto be useful in autoimmune diseases, including MS, are inhibitors ofosteopontin/Eta-1, as explained in detail in section V. “ClinicalApplications of the Modulatory Methods of the Invention”, D “AutoimmuneDiseases”, on page 51 to 53 of WO 00/63241.

Interferons are a subclass of cytokines that exhibit anti-inflammatory,antiviral and antiproliferative activity. On the basis of biochemicaland immunological properties, the naturally-occurring human interferonsare grouped into three classes: interferon alpha (leukocyte), interferonbeta (fibroblast) and interferon gamma (immune). Alpha-interferon iscurrently approved in the United States and other countries for thetreatment of hairy cell leukemia, venereal warts, Kaposi's Sarcoma (acancer commonly afflicting patients suffering from Acquired ImmuneDeficiency Syndrome (AIDS)), and chronic non-A, non-B hepatitis.

Further, interferons (IFNs) are glycoproteins produced by the body inresponse to a viral infection. They inhibit the multiplication ofviruses in protected cells. Consisting of a lower molecular weightprotein, IFNs are remarkably non specific in their action, i.e. IFNinduced by one virus is effective against a broad range of otherviruses. They are however species-specific, i.e. IFN produced by onespecies will only stimulate antiviral activity in cells of the same or aclosely related species. IFNs were the first group of cytokines to beexploited for their potential antitumour and antiviral activities.

The three major IFNs are referred to as IFN-α, IFN-β and IFN-γ. Suchmain kinds of IFNs were initially classified according to their cells oforigin (leucocyte, fibroblast or T cell). However, it became clear thatseveral types may be produced by one cell. Hence leucocyte IFN is nowcalled IFN-α, fibroblast IFN is IFN-β and T cell IFN is IFN-γ. There isalso a fourth type of IFN, lymphoblastoid IFN, produced in the “Namalwa”cell line (derived from Burkitt's lymphoma), which seems to produce amixture of both leucocyte and fibroblast IFN.

The Interferon unit has been reported as a measure of IFN activitydefined (somewhat arbitrarily) as the amount necessary to protect 50% ofthe cells against viral damage.

Every class of IFN contains several distinct types. IFN-β and IFN-γ areeach the product of a single gene. The differences between individualtypes seem to be mainly due to variations in glycosylation.

IFNs-α are the most diverse group, containing about 15 types. There is acluster of IFN-α genes on chromosome 9, containing at least 23 members,of which 15 are active and transcribed. Mature IFNs-α is notglycosylated.

IFNs-α and IFN-β are all the same length (165 or 166 amino acids) withsimilar biological activities. IFNs-γ are 146 amino acids in length, andresemble the α and β classes less closely. Only IFNs-γ can activatemacrophages or induce the maturation of killer T cells. In effect, thesenew types of therapeutic agents can be called biologic responsemodifiers (BRMs), because they have an effect on the response of theorganism to the tumour, affecting recognition via immunomodulation.

In particular, human fibroblast interferon (IFN-β) has antiviralactivity and can also stimulate natural killer cells against neoplasticcells. It is a polypeptide of about 20,000 Da induced by viruses anddouble-stranded RNAs. From the nucleotide sequence of the gene forfibroblast interferon, cloned by recombinant DNA technology, Derynk etal. (Derynk R. et al, 1980) deduced the complete amino acid sequence ofthe protein. It is 166 amino acid long.

Shepard et al. (Shepard H. M. et al. 1981) described a mutation at base842 (Cys→Tyr at position 141) that abolished its anti-viral activity,and a variant clone with a deletion of nucleotides 1119–1121.

Mark et al. (Mark D. F. et al, 1984) inserted an artificial mutation byreplacing base 469 (T) with (A) causing an amino acid switch fromCys→Ser at position 17. The resulting IFN-β was reported to be as activeas the ‘native’ IFN-β and stable during long-term storage (−70° C.).

Rebif® (recombinant human Interferon-β) is the latest development ininterferon therapy for multiple sclerosis (MS) and represents asignificant advance in treatment. Rebif® is interferon(IFN)-beta 1a,produced from mammalian cell lines and virtually identical to thenaturally occurring human molecule.

The mechanisms by which IFNs exert their effects are not completelyunderstood. However, in most cases they act by affecting the inductionor transcription of certain genes, thus affecting the immune system. Invitro studies have shown that IFNs are capable of inducing orsuppressing about 20 gene products

IFN-β may act by three major pathways in MS:

-   -   regulation of T-cell functions such as activation, proliferation        and suppressor cell function;    -   modulation of the production of cytokines: down-regulation of        proinflammatory cytokines and up-regulation of inhibitory,        antiinflammatory cytokines;    -   regulation of T-cell migration and infiltration into the CNS via        the BBB (blood brain barrier).

The PRISMS study has established the efficacy of Interferon beta-1agiven sub-cutaneously three times per week in the treatment ofRelapsing-Remitting Multiple Sclerosis(RR-MS). This study showed thatInterferon beta-1a can have a positive effect on the long-term course ofMS by reducing the number and severity of relapses and reducing theburden of the disease and disease activity as measured by MRI.(Randomised, Double-Blind, Placebo-Controlled Study of Interferonbeta-1a in Relapsing-remitting Multiple Sclerosis”. The Lancet 1998; 352(Nov. 7, 1998): 1498–1504.)

Citation of any document herein is not intended as an admission thatsuch document is pertinent prior art, or considered material to thepatentability of any claim of the present application. Any statement asto content or a date of any document is based on the informationavailable to applicants at the time of filing and does not constitute anadmission as to the correctness of such statement.

SUMMARY OF THE INVENTION

It is the object of the present invention to provide a novel means forthe treatment and/or prevention of a neurologic disease.

The invention is based on the finding that the protein osteopontinpromotes glial cell proliferation and differentiation, thus promotingmyelination and regeneration of nerves. In accordance with the presentinvention, it has further been found that osteopontin has a beneficialeffect in animal models of multiple sclerosis and peripheralneuropathies.

Therefore, the present invention relates to the use of osteopontin, orof an agonist of osteopontin activity, in a neurologic disease, such astraumatic nerve injury, stroke, demyelinating diseases of the CNS orPNS, neuropathies and neurodegenerative diseases.

In accordance with the present invention, osteopontin may also be usedin combination with an interferon for treatment and/or prevention ofneurologic diseases. The use of nucleic acid molecules, and expressionvectors comprising osteopontin, and of cells expressing osteopontin, fortreatment and/or prevention of a neurologic disease is also within thepresent invention. The invention further provides pharmaceuticalcompositions comprising osteopontin and an interferon, optionallytogether with one or more pharmaceutically acceptable excipients.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a histogram depicting the levels of osteopontin expressionafter different times of cuprizone treatment, as measured by TaqMan®analysis. 3/5 w. Cup=three or five weeks of cuprizone treatment, 5w.cup+1/3/6w.=five weeks of cuprizone treatment and after withdrawal ofcuprizone one/three or six weeks of recovery.

FIG. 1B shows the fold regulation of osteopontin, MBP and PLP mRNAcompared to control C1 levels as measured by TaqMan® in different stagesof cerebellar development. C1 to 20=postnatal cerebellum at day 1 to 20,CA=adult cerebellum.

FIG. 2 schematically depicts the structure of osteopontin and its knownisoforms as well as C and N terminal constructs.

FIG. 3 schematically depicts the plasmid Pac containing the codingsequence for osteopontin.

FIG. 4 shows a histogram illustrating the fold upregulation ofosteopontin mRNA in oligodendrocyte cell line oli-neu treated with cAMPfor 6 h (1), 2 d (2), 6 d (3) or 10 d (4) as compared to control.Columns 5 and 6 depict the osteopontin mRNA levels from a cuprizoneexperiment. (5): 3 weeks of cuprizone treatment, (6): 5 weeks ofcuprizone treatment.

FIG. 5 shows schematically the plasmid pDEST 12.2 comprising theosteopontin coding sequence.

FIG. 6 shows schematically the plasmid pDEST 12.2 comprising theosteopontin coding sequence plus the coding sequence of EGFP, afluorescent marker.

FIG. 7 shows schematically the plasmid pDEST 12.2 comprising theosteopontin coding sequence with a HIS-tag.

FIG. 8 shows the proliferation of oli-neu cells after insulin starvationand 24 hrs treatment with osteopontin expressed in baculovirus(Baculo-OPN) or HEK cell expressed osteopontin (HEK-OPN). Read-out isfluorescence of Alamar Blue, a dye staining living cells.

FIG. 9 shows the dose response curve of proliferation of insulin starvedoli-neu cells after 24 hours of treatment with baculovirus expressedosteopontin (BAC-OPN) or HEK cell expressed osteopontin (HEK-OPN).

FIG. 10 shows the proliferation of oli-neu cells after insulinstarvation and treatment with either full-length baculovirus expressedosteopontin (BacOPN) or an N-terminal fragment of osteopontin(N-terminal BacOPN).

FIGS. 11A–D show the MBP immunohistochemistry in mixed cortical culturestreated with 100 nM of baculovirus expressed recombinant osteopontin.FIG. 11A=control; FIG. 11B=OPN treated; FIG. 11C=magnification of FIG.11B; FIG. 11D=another field of OPN treated mixed cortical cells, whereno axons are visible.

FIG. 12 shows the increase of MBP protein in myelinating, mixed corticalcultures after LIF and baculovirus expressed osteopontin treatment asmeasured by ELISA.

FIG. 13 shows the proliferation of CG4 cells after treatment withdifferent dosages (10 pM, 10 nM, 100 nM) of in vitro phosphorylated E.coli expressed osteopontin (OPN-E. coli) or baculovirus expressedosteopontin (OPN Bac).

FIG. 14 shows the perivascular inflammatory infiltrates present inspinal cords of EAE mice treated subcutaneously with vehicle (PBS),vehicle plus 0.1% BSA, 1, 10 or 100 μg/kg of AS900011 (osteopontin) orwith a combination of 100 μg/kg AS900011 and 20000 U/mouse murineinterferon beta (mIFNβ), or 20000 U/mouse mIFNβ alone.

FIG. 15 shows the percentage of demyelinating area present in spinalcords of EAE mice treated subcutaneously with vehicle (PBS), vehicleplus 0.1% BSA, 1, 10 or 100 μg/kg of AS900011 (osteopontin) or with acombination of 100 μg/kg AS900011 and 20000 U/mouse murine interferonbeta (mIFNβ) or 20000 U/mouse mIFNβ alone.

FIG. 16 shows clinical scores at the end of treatment, the inflammatoryinfiltrations and the demyelination in EAE mice treated subcutaneouslywith vehicle (PBS), vehicle plus 0.1% BSA, 1, 10 or 100 μg/kg ofAS900011 (osteopontin) or with a combination of 100 μg/kg AS900011 and20000 U/mouse murine interferon beta (mIFNβ) or 20000 U/mouse mIFNβalone.

FIG. 17 shows the body weight of neuropathic mice induced by staticnerve crush treated with vehicle, 1, 10 or 100 μg/kg of osteopontin(Ost), 10 μg/kg of a positive control compound (4-MC) or 100 μg/kg ofdenatured osteopontin (Ost-D).

FIG. 18 shows the amplitude of the compound muscle action potential inthe neuropathic mice treated with vehicle, 1, 10 or 100 μg/kg ofosteopontin (Ost). 10 μg/kg of a positive control compound (4-MC) or 100μg/kg of denatured osteopontin (Ost-D).

FIG. 19 shows the latency of the compound muscle action potential in theneuropathic mice treated with vehicle, 1, 10 or 100 μg/kg of osteopontin(Ost), 10 μg/kg of a positive control compound (4-MC) or 100 μg/kg ofdenatured osteopontin (Ost-D).

FIG. 20 shows the duration of the compound muscle action potential inthe neuropathic mice treated with vehicle, 1, 10 or 100 μg/kg ofosteopontin (Ost), 10 μg/kg of a positive control compound (4-MC) or 100μg/kg of denatured osteopontin (Ost-D).

FIG. 21 shows the percentage of degenerated fibers in the neuropathicmice treated with vehicle, 1, 10 or 100 μg/kg of osteopontin (Ost), 10μg/kg of a positive control compound (4-MC) or 100 μg/kg of denaturedosteopontin (Ost-D).

FIG. 22 shows total number of fibers per field in the neuropathic micetreated with vehicle, 1, 10 or 100 μg/kg of osteopontin (Ost), 10 μg/kgof a positive control compound (4-MC) or 100 μg/kg of denaturedosteopontin (Ost-D).

DETAILED DESCRIPTION OF THE INVENTION

The present invention is based on the finding that osteopontin isdifferentially expressed during oligodendrocyte differentiation andduring the development of the cerebellum. It has further been found thatexpression of osteopontin cDNA in oligodendrocytes leads to adifferentiated phenotype of these cells in vitro. Upon expression ofosteopontin, oligodendrocytes display a phenotype similar to thephenotype of a differentiating, myelinating cell. In addition to thesein vitro findings, it has been shown that osteopontin, and in particularthe combination of osteopontin and an interferon, have a beneficialeffect in an established model of multiple sclerosis. In an experimentalmodel of peripheral neuropathy, osteopontin had a pronounced beneficialeffect on nerve activity, and significantly reduced the percentage ofdegeneration and enhanced the extent of myelination.

The experimental evidence presented herein therefore provides for a newpossibility of treating neurologic diseases, in particular those linkedto nervous and glial cell function. These findings are particularlysurprising because WO 00/63241 teaches to inhibit osteopontin in orderto treat multiple sclerosis.

The invention therefore relates to the use of osteopontin, or of anagonist of osteopontin activity, for the manufacture of a medicament fortreatment and/or prevention of neurologic diseases.

The term “osteopontin”, as used herein, relates to full-length humanosteopontin, having the amino acid sequence that has been known sincethe late eighties (Oldberg et al., 1986; Kiefer et al., 1989). Thesequence of human osteopontin is-reported herein as SEQ ID NO: 1 of theannexed sequence listing. The term “osteopontin”, as used herein,further relates to any osteopontin derived from animals, such as murine,bovine, or rat osteopontin, as long as there is sufficient identity inorder to maintain osteopontin activity, and as long as the resultingmolecule will not be immunogenic in humans.

The term “osteopontin”, as used herein, further relates to biologicallyactive muteins and fragments, such as the naturally occurring isoformsof osteopontin. Osteopontin is expressed in functionally distinct formsthat differ at the level of transcription (alternative splicing) andposttranslational modifications (phosphorylation, glycosylation). Threesplice variants of OPN are known so far, designated OPN-a (herein alsocalled “full-length” osteopontin), OPN-b and OPN-c (SEQ ID NO: 1, 2 and3 of the annexed sequence listing, also depicted in FIG. 2). Theisoforms were described e.g. by Kon et al. (2000), and characterizede.g. by Saitoh et al. (1995) and Kon et al. (2002).

A thrombin cleavage leads to two in vivo proteolytic cleavage fragmentscomprising the N- and C-terminal portions of the protein.Phosphorylation of osteopontin, in particular of the C-terminal portionof the proteins, may be important for osteopontin function. The term“osteopontin” as used herein, is therefore also meant to encompassesthese proteolytic fragments and differentially phosphorylatedosteopontin forms.

The term “osteopontin”, as used herein, further encompasses isoforms,muteins, fused proteins, functional derivatives, active fractions orfragments, or circularly permutated derivatives, or salts thereof. Theseisoforms, muteins, fused proteins or functional derivatives, activefractions or fragments, or circularly permutated derivatives retain thebiological activity of osteopontin. Preferably, they have a biologicalactivity, which is improved as compared to wild type osteopontin.

The term “agonist of osteopontin activity”, as used herein, relates to amolecule stimulating or imitating osteopontin activity, such asagonistic antibodies of the osteopontin receptor, or small molecularweight agonists activating signaling through an osteopontin receptor.Osteopontin mediates its function through at least two groups ofreceptors. First, it interacts with αv-integrins (αvβ3 and αvβ5 integrinreceptors via an RGD (Arg-Gly-Asp) cell attachment motif under thepositive influence of manganese (Kunicki et al., 1997). Second, itinteracts with CD44 variant isoforms v6-v10. The C-terminal part ofosteopontin is believed to be involved in, the interaction with CD44,while the N-terminal part of osteopontin is believed to be involved ininteraction with integrin receptors, proliferation, survival anddifferentiation of macrophages. The N-terminal portion of osteopontinalso induces IL-12 and IL-10 release. Any agonist, stimulator orenhancer, of any of these receptors is encompassed by the term “agonistof OPN activity”, as used herein.

The term “agonist of osteopontin activity”, as used herein, furtherrefers to agents enhancing osteopontin mediated activities, such aspromotion of cell attachment to extracellular matrix components, themorphogenesis of cells of the oligodendrocyte lineage intomyelinproducing cells, to promote the recruitment, proliferation,differentiation or maturation of cells of the oligodendrocyte lineage(such as progenitors or precursor cells), to promote the protection ofcells of the oligodendrocyte lineage from apoptosis and cell injury.

The terms “treating” and “preventing”, as used herein, should beunderstood as preventing, inhibiting, attenuating, ameliorating orreversing one or more symptoms or cause(s) of neurologic disease, aswell as symptoms, diseases or complications accompanying neurologicdisease. When “treating” neurologic disease, the substances according tothe invention are given after onset of the disease, “prevention” relatesto administration of the substances before signs of disease can be notedin the patient.

The term “neurologic diseases”, as used herein encompasses all knownneurologic diseases or disorders, or injuries of the CNS or PNS,including those described in detail in the “Background of theinvention”.

Neurologic diseases comprise disorders linked to dysfunction of the CNSor PNS, such as diseases related to neurotransmission, headache, traumaof the head, CNS infections, neuro-ophthalmologic and cranial nervedisorders, function and dysfunction of the cerebral lobes disorders ofmovement, stupor and coma, demyelinating diseases, delirium anddementia, craniocervical junction abnormalities, seizure disorders,spinal cord disorders, sleep disorders, disorders of the peripheralnervous system, cerebrovascular disease, or muscular disorders. Fordefinitions of these disorders, see e.g.www.merck.com/pubs/manual/section14/sec14.htm.

Preferably, the neurologic diseases of the invention are selected fromthe group consisting of traumatic nerve injury, stroke, demyelinatingdiseases of the CNS or PNS and neurodegenerative diseases.

Traumatic nerve injury may concern the PNS or the CNS, it may be brainor spinal cord trauma, including paraplegia, as described in the“background of the invention” above.

Stroke may be caused by hypoxia or by ischemia of the brain. It is alsocalled cerebrovascular disease or accident. Stroke may involve loss ofbrain functions (neurologic deficits) caused by a loss of bloodcirculation to areas of the brain. Loss of blood circulation may be dueto blood clots that form in the brain (thrombus), or pieces ofatherosclerotic plaque or other material that travel to the brain fromanother location (emboli). Bleeding (hemorrhage) within the brain maycause symptoms that mimic stroke. The most common cause of a stroke isstroke secondary to atherosclerosis (cerebral thrombosis), and thereforethe invention also relates to the treatment of atherosclerosis.

Peripheral Neuropathy may be related to a syndrome of sensory loss,muscle weakness and atrophy, decreased deep tendon reflexes, andvasomotor symptoms, alone or in any combination. Neuropathy may affect asingle nerve (mononeuropathy), two or more nerves in separate areas(multiple mononeuropathy), or many nerves simultaneously(polyneuropathy). The axon may be primarily affected (e.g. in diabetesmellitus, Lyme disease, or uremia or with toxic agents), or the myelinsheath or Schwann cell (e.g. in acute or chronic inflammatorypolyneuropathy, leukodystrophies, or Guillain-Barré syndrome). Furtherneuropathies, which may be treated in accordance with the presentinvention, may e.g. be due to lead toxicity, dapsone use, tick bite,porphyria, or Guillain-Barré syndrome, and they may primarily affectmotor fibers. Others, such as those due to dorsal root ganglionitis ofcancer, leprosy, AIDS, diabetes mellitus, or chronic pyridoxineintoxication, may primarily affect the dorsal root ganglia or sensoryfibers, producing sensory symptoms. Cranial nerves may also be involved,such as e.g. in Guillain-Barré syndrome, Lyme disease, diabetesmellitus, and diphtheria.

Alzheimer's disease is a disorder involving deterioration in mentalfunctions resulting from changes in brain tissue. This may includeshrinking of brain tissues, primary degenerative dementia and diffusebrain atrophy. Alzheimer's disease is also called seniledementia/Alzheimer's type (SDAT).

Parkinsons's disease is a disorder of the brain including shaking anddifficulty with walking, movement, and coordination. The disease isassociated with damage to a part of the brain that controls musclemovement, and it is also called paralysis agitans or shaking palsy.

Huntington's Disease is an inherited, autosomal dominant neurologicdisease.

Amyptrophic Lateral Sclerosis, ALS, is a disorder causing progressiveloss of nervous control of voluntary muscles, including of destructionof nerve cells in the brain and spinal cord. Amyotrophic LateralSclerosis, also called Lou Gehrig's disease, is a disorder involvingloss of the use and control of muscles.

Multiple Sclerosis (MS) is an inflammatory demyelinating disease of thecentral nervous system (CNS) that takes a relapsing-remitting or aprogressive course. MS is not the only demyelinating disease. Itscounterpart in the peripheral nervous system (PNS) is chronicinflammatory demyelinating polyradiculoneuropathy (CIDP). In addition,there are acute, monophasic disorders, such as the inflammatorydemyelinating polyradiculoneuropathy termed Guillain-Barré syndrome(GBS) in the PNS, and acute disseminated encephalomyelitis (ADEM) in theCNS.

Further neurologic disorders comprise neuropathies with abnormalmyelination, such as the ones listed in the “Background of theinvention” above, as well as carpal tunnel syndrome. Traumatic nerveinjury may be accompanied by spinal column orthopedic complications, andthose are also within the diseases in accordance with the presentinvention.

Neurologic disorders may further be due to congenital metabolicdisorders. In a preferred embodiment of the invention, the neurologicdisease is therefore due to a congenital metabolic deficit.

The congenital metabolic disorders encompassed by the present inventionmay be e.g. phenylketonuria and other aminoacidurias, Tay-Sachs,Niemann-Pick, and Gaucher's diseases, Hurler's syndrome; Krabbe'sdisease and other leukodystrophies. They may affect the developingmyelin sheath, mainly in the CNS.

Neurologic diseases caused by congenital metabolic disorders have alsobeen discussed in detail in the “Background of the invention”.

Less well known neurologic diseases are also within the scope of thepresent invention, such as neurofibromatosis, or Multiple System Atrophy(MSA). Further disorders that may be treated in accordance with thepresent invention, have been described in detail in the “Background ofthe invention” above.

In a further preferred embodiment, the neurologic disease is aperipheral neuropathy, most preferably diabetic neuropathy. Chemotherapyassociated neuropathies are also preferred in accordance with thepresent invention.

The term “diabetic neuropathy” relates to any form of diabeticneuropathy, or to one or more symptom(s) or disorder(s) accompanying orcaused by diabetic neuropathy, or complications of diabetes affectingnerves as described in detail in the “Background of the invention2above. Diabetic neuropathy may be a polyneuropathy. In diabeticpolyneuropathy, many nerves are simultaneously affected. The diabeticneuropathy may also be a mononeuropathy. In focal mononeuropathy, forinstance, the disease affects a single nerve, such as the oculomotor orabducens cranial nerve. It may also be multiple mononeuropathy when twoor more nerves are affected in separate areas.

In yet a further preferred embodiment, the neurologic disorder is ademyelinating disease. Demyelinating diseases preferably comprisedemyelinating conditions of the CNS, like acute disseminatedencephalomyelitis (ADEM) and multiple sclerosis (MS), as well asdemyelinating diseases of the peripheral nervous system (PNS). Thelatter comprise diseases such as chronic inflammatory demyelinatingpolyradiculoneuropathy. (CIDP and acute, monophasic disorders, such asthe inflammatory demyelinating: polyradiculoneuropathy termedGuillain-Barré syndrome (GBS).

A further preferred embodiment of the invention relates to the treatmentand/or prevention of a neurodegenerative disease. The neurodegenerativedisease is selected from the group consisting of Alzheimer's disease,Parkinson's disease, Huntington's disease and ALS.

Preferably, the osteopontin is selected from a peptide, a polypeptide ora protein selected from the group consisting of:

(a) A polypeptide comprising SEQ ID NO: 1;

(b) A polypeptide comprising amino acids 1 to 168 or 170 of SEQ ID NO:1;

(c) A polypeptide comprising amino acids 1 to 16 and 170 to 314 of SEQID NO: 1;

(d) A polypeptide comprising amino acids 170 to 314 of SEQ ID NO: 1;

(e) A polypeptide comprising SEQ ID NO: 2;

(f) A polypeptide comprising SEQ ID NO: 3;

(g) A mutein of any of (a) to (f), wherein the amino acid sequence hasat least 40% or 50% or 60% or 70% or 80% or 90% identity to at least oneof the sequences in (a) to (f);

(h) A mutein of any of (a) to (f) which is encoded by a DNA sequencewhich hybridizes to the complement of the native DNA sequence encodingany of (a) to (f) under moderately stringent conditions or under highlystringent conditions;

(i) A mutein of any of (a) to (f) wherein any changes in the amino acidsequence are conservative amino acid substitutions to the amino acidsequences in (a) to (f);

(j) a salt or an isoform, fused protein, functional derivative, activefraction or circularly permutated derivative of any of (a) to (f).

Active fractions or fragments may comprise any portion or domain of anyof the osteopontin isoforms, such as an N-terminal portion or aC-terminal portion, or any of OPN-a, -b, or -c, as shown in FIG. 2. TheGRGDS motif may be present, or absent, or mutated. The heparin bindingsite may be mutated so as to render osteopontin devoid ofheparin-binding. Full length osteopontin, or any active fragmentthereof, may be phosphorylated at one or more of the following serineresidues, such as the serine residues at the following positions: 8, 10,11, 33, 46, 47, 60, 62, 65, 83, 86, 89, 92, 101, 104, 107, 110, 113,153, 155, 175, 179, 199, 203, 208, 212, 218, 223, 227, 238, 242, 247,251, 254, 259, 264, 275, 287, 292, 294, 295. Additionally, the serinephosphorylation sites may be mutated from serine to glutamate residues,in order to mimic phosphorylation.

The person skilled in the art will appreciate that even smaller portionsof osteopontin may be enough to exert its function, such as an activepeptide comprising the essential amino acid residues required forosteopontin function.

The person skilled in the art will further appreciate that muteins,salts, isoforms, fused proteins, functional derivatives of osteopontin,active fractions or circularly permutated derivatives of osteopontin,will retain a similar, or even better, biological activity ofosteopontin. The biological activity of osteopontin and muteins,isoforms, fused proteins or functional derivatives, active fractions orfragments, circularly permutated derivatives, or salts thereof, may bemeasured in a co-culturing assay, such as the one described below inExample 8. Mixed cortical cultures contain oligodendrocytes, as well asother CNS derived cells (such as neurons, astrocytes, microglia), andinduce or up-regulate the typical genes involved in myelination, likeP0, MBP or MAG, upon incubation with OPN or the mutein, isoform,fragment, active fraction, functional derivative or salt. Expression ofthese genes can be measured by quantitative real time RT-PCR (TaqMan®RT-PCR) analysis, which is explained in detail in the examples below. Afurther simple assay to measure OPN activity is an oligodendrocyteproliferation assay, comprising incubating an adequate oligodendrocytecell line, such as oli-neu or CG4 cells, with OPN or the mutein,isoform, fragment, active fraction, functional derivative or salt, asdescribed in Example 7 below, for example.

Preferred active fractions have an activity which is equal or betterthan the activity of full-length osteopontin, or which have furtheradvantages, such as a better stability or a lower toxicity orimmunogenicity, or they are easier to produce in large quantities, oreasier to purify. The person skilled in the art will appreciate thatmuteins, active fragments and functional derivatives can be generated bycloning the corresponding cDNA in appropriate plasmids and testing themin the co-culturing assay, as mentioned above.

The proteins according to the present invention may be glycosylated ornon-glycosylated, they may be derived from natural sources, such as bodyfluids, or they may preferably be produced recombinantly. Recombinantexpression may be carried out in prokaryotic expression systems such asE. coli, or in eukaryotic, such as insect cells, and preferably inmammalian expression systems, such as CHO-cells or HEK-cells.

As used herein the term “muteins” refers to analogs of osteopontin, inwhich one or more of the amino acid residues of a natural osteopontinare replaced by different amino acid residues, or are deleted, or one ormore amino acid residues are added to the natural sequence ofosteopontin, without changing considerably the activity of the resultingproducts as compared with the wild-type osteopontin. These muteins areprepared by known synthesis and/or by site-directed mutagenesistechniques, or any other known technique suitable therefor.

Muteins of osteopontin, which can be used in accordance with the presentinvention, or nucleic acid coding thereof, include a finite set ofsubstantially corresponding sequences as substitution peptides orpolynucleotides which can be routinely obtained by one of ordinary skillin the art, without undue experimentation, based on the teachings andguidance presented herein.

Muteins in accordance with the present invention include proteinsencoded by a nucleic acid, such as DNA or RNA, which hybridizes to DNAor RNA, which encodes OPN, in accordance with the present invention,under moderately or highly stringent conditions. The term “stringentconditions” refers to hybridization and subsequent washing conditions,which those of ordinary skill in the art conventionally refer to as“stringent”. See Ausubel et al., Current Protocols in Molecular Biology,supra, Interscience, N.Y., §§6.3 and 6.4 (1987, 1992), and Sambrook etal.(Sambrook, J. C., Fritsch, E. F., and Maniatis, T. (1989) MolecularCloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press, ColdSpring Harbor, N.Y.).

Without limitation, examples of stringent conditions include washingconditions 12–20° C. below the calculated Tm of the hybrid under studyin, e.g., 2×SSC and 0.5% SDS for 5 minutes, 2×SSC and 0.1% SDS for 15minutes; 0.1×SSC and 0.5% SDS at 37° C. for 30–60 minutes and then, a0.1×SSC and 0.5% SDS at 68° C. for 30–60 minutes. Those of ordinaryskill in this art understand that stringency conditions also depend onthe length of the DNA sequences, oligonucleotide probes (such as 10–40bases) or mixed oligonucleotide probes. If mixed probes are used, it ispreferable to use tetramethyl ammonium chloride (TMAC) instead of SSC.See Ausubel, supra.

In a preferred embodiment, any such mutein has at least 40% identity orhomology with the sequence of SEQ ID NO: 1, 2 or 3 of the annexedsequence listing. More preferably, it has at least 50%, at least 60%, atleast 70%, at least 80% or, most preferably, at least 90% identity orhomology thereto.

Identity reflects a relationship between two or more polypeptidesequences or two or more polynucleotide sequences, determined bycomparing the sequences. In general, identity refers to an exactnucleotide to nucleotide or amino acid to amino acid correspondence ofthe two polynucleotides or two polypeptide sequences, respectively, overthe length of the sequences being compared.

For sequences where there is not an exact correspondence, a “% identity”may be determined. In general, the two sequences to be compared arealigned to give a maximum correlation between the sequences. This mayinclude inserting “gaps” in either one or both sequences, to enhance thedegree of alignment. A % identity may be determined over the wholelength of each of the sequences being compared (so-called global,alignment), that is particularly suitable for sequences of the same orvery similar length, or over shorter, defined lengths (so-called localalignment), that is more suitable for sequences of unequal length.

Methods for comparing the identity and homology of two or more sequencesare well known in the art. Thus for instance, programs available in theWisconsin Sequence Analysis Package, version 9.1 (Devereux J et al1984), for example the programs BESTFIT and GAP, may be used todetermine the % identity between two polynucleotides and the % identityand the % homology between two polypeptide sequences. BESTFIT uses the“local homology” algorithm of Smith and Waterman (1981) and finds thebest single region of similarity between two sequences. Other programsfor determining identity and/or similarity between sequences are alsoknown in the art, for instance the BLAST family of programs (Altschul SF et al, 1990, Altschul S F et al, 1997, accessible through the homepage of the NCBI at www.ncbi.nlm.nih.gov) and FASTA (Pearson W R, 1990;Pearson 1988).

Preferred changes for muteins in accordance with the present inventionare what are known as “conservative” substitutions. Conservative aminoacid substitutions of osteopontin polypeptides, may include synonymousamino acids within a group which have sufficiently similarphysicochemical properties that substitution between members of thegroup will preserve the biological function of the molecule (Grantham,1974). It is clear that insertions and deletions of amino acids may alsobe made in the above-defined sequences without altering their function,particularly if the insertions or deletions only involve a few aminoacids, e.g. under thirty, and preferably under ten, and do not remove ordisplace amino acids which are critical to a functional conformation,e.g. cysteine residues. Proteins and muteins produced by such deletionsand/or insertions come within the purview of the present invention.

Preferably, the synonymous amino acid groups are those defined in TableI. More preferably, the synonymous amino acid groups are those definedin Table II; and most preferably the synonymous amino acid groups arethose defined in Table III.

TABLE I Preferred Groups of Synonymous Amino Acids Amino Acid SynonymousGroup Ser Ser, Thr, Gly, Asn Arg Arg, Gln, Lys, Glu, His Leu Ile, Phe,Tyr, Met, Val, Leu Pro Gly, Ala, Thr, Pro Thr Pro, Ser, Ala, Gly, His,Gln, Thr Ala Gly, Thr, Pro, Ala Val Met, Tyr, Phe, Ile, Leu, Val GlyAla, Thr, Pro, Ser, Gly Ile Met, Tyr, Phe, Val, Leu, Ile Phe Trp, Met,Tyr, Ile, Val, Leu, Phe Tyr Trp, Met, Phe, Ile, Val, Leu, Tyr Cys Ser,Thr, Cys His Glu, Lys, Gln, Thr, Arg, His Gln Glu, Lys, Asn, His, Thr,Arg, Gln Asn Gln, Asp, Ser, Asn Lys Glu, Gln, His, Arg, Lys Asp Glu,Asn, Asp Glu Asp, Lys, Asn, Gln, His, Arg, Glu Met Phe, Ile, Val, Leu,Met Trp Trp

TABLE II More Preferred Groups of Synonymous Amino Acids Amino AcidSynonymous Group Ser Ser Arg His, Lys, Arg Leu Leu, Ile, Phe, Met ProAla, Pro Thr Thr Ala Pro, Ala Val Val, Met, Ile Gly Gly Ile Ile, Met,Phe, Val, Leu Phe Met, Tyr, Ile, Leu, Phe Tyr Phe, Tyr Cys Cys, Ser HisHis, Gln, Arg Gln Glu, Gln, His Asn Asp, Asn Lys Lys, Arg Asp Asp, AsnGlu Glu, Gln Met Met, Phe, Ile, Val, Leu Trp Trp

TABLE III Most Preferred Groups of Synonymous Amino Acids Amino AcidSynonymous Group Ser Ser Arg Arg Leu Leu, Ile, Met Pro Pro Thr Thr AlaAla Val Val Gly Gly Ile Ile, Met, Leu Phe Phe Tyr Tyr Cys Cys, Ser HisHis Gln Gln Asn Asn Lys Lys Asp Asp Glu Glu Met Met, Ile, Leu Trp Met

Examples of production of amino acid substitutions in proteins which canbe used for obtaining muteins of osteopontin, polypeptides or proteins,for use in the present invention include any known method steps, such aspresented in U.S. Pat. Nos. 4,959,314, 4,588,585 and 4,737,462, to Market al; U.S. Pat. No. 5,116,943 to Koths et al., U.S. Pat. No. 4,965,195to Namen et al; U.S. Pat. No. 4,879,111 to Chong et al; and U.S. Pat.No. 5,017,691 to Lee et al; and lysine substituted proteins presented inU.S. Pat. No. 4,904,584 (Shaw et al).

The term “fused protein” refers to a polypeptide comprising osteopontin,or a mutein or fragment thereof, fused with another protein, which, e.g.has an extended residence time in body fluids. An osteopontin may thusbe fused to another protein, polypeptide or the like, e.g. animmunoglobulin or a fragment thereof.

“Functional derivatives” as used herein, cover derivatives ofosteopontin, and their muteins and fused proteins, which may be preparedfrom the functional groups which occur as side chains on the residues orthe N- or C-terminal groups, by means known in the art, and are includedin the invention as long as they remain pharmaceutically acceptable,i.e. they do not destroy the activity of the protein which issubstantially similar to the activity of osteopontin, and do not confertoxic properties on compositions containing it.

These derivatives may, for example, include polyethylene glycolside-chains, which may mask antigenic sites and extend the residence ofan osteopontin in body fluids. Other derivatives include aliphaticesters of the carboxyl groups, amides of the carboxyl groups by reactionwith ammonia or with primary or secondary amines, N-acyl derivatives offree amino groups of the amino acid residues formed with acyl moieties(e.g alkanoyl or carbocyclic aroyl groups) or O-acyl derivatives of freehydroxyl groups (for example that of seryl or threonyl residues) formedwith acyl moieties.

As “active fractions” of osteopontin, muteins and fused proteins, thepresent invention covers any fragment or precursors of the polypeptidechain of the protein molecule alone or together with associatedmolecules or residues linked thereto, e.g. sugar or phosphate residues,or aggregates of the protein molecule or the sugar residues bythemselves, provided said fraction has substantially similar activity toosteopontin.

The term “salts” herein refers to both salts of carboxyl groups and toacid addition salts of amino groups of OPN molecule or analogs thereof.Salts of a carboxyl group may be formed by means known in the art andinclude inorganic salts, for example, sodium, calcium, ammonium, ferricor zinc salts, and the like, and salts with organic bases as thoseformed, for example, with amines, such as triethanolamine, arginine orlysine, piperidine, procaine and the like. Acid addition salts include,for example, salts with mineral acids, such as, for example,hydrochloric acid or sulfuric acid, and salts with organic acids, suchas, for example, acetic acid or oxalic acid. Of course, any such saltsmust retain the biological activity of OPN relevant to the presentinvention, i.e., exert a proliferative effect on oligodendrocytes.

In a preferred embodiment of the invention, osteopontin is fused to acarrier molecule, a peptide or a protein that promotes the crossing ofthe blood brain barrier (“BBB”). This serves for proper targeting of themolecule to the site of action in those cases, in which the CNS isinvolved in the disease. Modalities for drug delivery through the BBBentail disruption of the BBB, either by osmotic means or biochemicallyby the use of vasoactive substances such as bradykinin. Other strategiesto go through the BBB may entail the use of endogenous transportsystems, including carrier-mediated transporters such as glucose andamino acid carriers; receptor-mediated transcytosis for insulin ortransferrin; and active efflux transporters such as p-glycoprotein.Strategies for drug delivery behind the BBB further includeintracerebral implantation.

Functional derivatives of osteopontin may be conjugated to polymers inorder to improve the properties of the protein, such as the stability,half-life, bioavailability, tolerance by the human body, orimmunogenicity. To achieve this goal, osteopontin may be linked e.g. toPolyethlyenglycol (PEG). PEGylation may be carried out by known methods,described in WO 92/13095, for example.

Therefore, in a preferred embodiment of the present invention,osteopontin is PEGylated.

In a further preferred embodiment of the invention, the fused proteincomprises an immunoglobulin (Ig) fusion. The fusion may be direct, orvia a short linker peptide which can be as short as 1 to 3 amino acidresidues in length or longer, for example, 13 amino acid residues inlength. Said linker may be a tripeptide of the sequence E-F-M(Glu-Phe-Met), for example, or a 13-amino acid linker sequencecomprising Glu-Phe-Gly-Ala-Gly-Leu-Val-Leu-Gly-Gly-Gln-Phe-Met (SEQ IDNO: 6) introduced between osteopontin sequence and the immunoglobulinsequence, for instance. The resulting fusion protein has improvedproperties, such as an extended residence time in body fluids(half-life), or an increased specific activity, increased expressionlevel. The Ig fusion may also facilitate purification of the fusedprotein.

In a yet another preferred embodiment, osteopontin is fused to theconstant region of an Ig molecule. Preferably, it is fused to heavychain regions, like the CH2 and CH3 domains of human IgG1, for example.Other isoforms of Ig molecules are also suitable for the generation offusion proteins according to the present invention, such as isoformsIgG₂ or IgG₄, or other Ig classes, like IgM, for example. Fusionproteins may be monomeric or multimeric, hetero- or homomultimeric. Theimmunoglobulin portion of the fused protein may be further modified in away as to not activate complement binding or the complement cascade orbind to Fc-receptors.

The invention further relates to the use of a combination of osteopontinand an immunosuppressive agent for the manufacture of a medicament fortreatment and/or prevention of neurologic disorders, for simultaneous,sequential or separate use. Immunosuppressive agents may be steroids,methotrexate, cyclophosphamide, anti-leukocyte antibodies (such asCAMPATH-1), and the like.

The invention further relates to the use of a combination of osteopontinand an interferon for the manufacture of a medicament for treatmentand/or prevention of neurologic disorders, for simultaneous, sequential,or separate use.

The term “interferon”, as used in the present patent application, isintended to include any molecule defined as such in the literature,comprising for example any kinds of IFNs mentioned in the above section“Background of the Invention”. The interferon may preferably be human,but also derived from other species, as long as the biological activityis similar to human interferons, and the molecule is not immunogenic inman.

In particular, any kinds of IFN-α, IFN-β and IFN-γ are included in theabove definition. IFN-β is the preferred IFN according to the presentinvention.

The term “interferon-beta (IFN-β)”, as used in the present invention, isintended to include human fibroblast interferon, as obtained byisolation from biological fluids or as obtained by DNA recombinanttechniques from prokaryotic or eukaryotic host cells as well as itssalts, functional derivatives, variants, analogs and fragments.

“Functional derivatives”, as used herein, covers derivatives which maybe prepared from the functional groups which occur as side chains on theresidues or the N- or C-terminal groups, by means known in the art, andare included in the invention as long as they remain pharmaceuticallyacceptable, i.e., they do not destroy the biological activity of theproteins as described above, such as the ability to bind thecorresponding receptor and initiate receptor signaling, and do, notconfer toxic properties on compositions containing it. Derivatives mayhave chemical moieties, such as carbohydrate or phosphate residues,provided such a derivative retains the biological activity of theprotein and remains pharmaceutically acceptable.

For example, derivatives may include aliphatic esters of the carboxylgroups, amides of the carboxyl groups by reaction with ammonia or withprimary or secondary amines, N-acyl derivatives or free amino groups ofthe amino acid residues formed with acyl moieties (e.g. alkanoyl orcarbocyclic aroyl groups) or O-acyl derivatives of free hydroxyl group(e.g. that of seryl or threonyl residues) formed with acyl moieties.Such derivatives may also include for example, polyethylene glycolside-chains which may mask antigenic sites and extend the residence ofthe molecule in body fluids.

Of particular importance is a protein that has been derivatized orcombined with a complexing agent to be long lasting. For example,PEGylated versions, as mentioned above, or proteins geneticallyengineered to exhibit long lasting activity in the body, can be usedaccording to the present invention.

The term “derivatives” is intended to include only those derivativesthat do not change one amino acid to another of the twentycommonly-occurring natural amino acids.

The term “salts” herein refers to both salts of carboxyl groups and toacid addition salts of amino groups of the proteins described above oranalogs thereof. Salts of a carboxyl group may be formed by means knownin the art and include inorganic salts, for example, sodium, calcium,ammonium, ferric or zinc salts, and the like, and salts with organicbases as those formed, for example, with amines, such astriethanolamine, arginine or lysine, piperidine, procaine and the like.Acid addition salts include, for example, salts with mineral acids, suchas, for example, hydrochloric acid or sulfuric acid, and salts withorganic acids, such as, for example, acetic acid or oxalic acid. Ofcourse, any such salts must retain the biological activity of theproteins (osteopontin and IFN-beta, respectively) relevant to thepresent invention, i.e., the ability to bind to the correspondingreceptor and initiate receptor signaling.

Interferons may also be conjugated to polymers in order to improve thestability of the proteins. A conjugate between Interferon β and thepolyol Polyethlyenglycol (PEG) has been described in WO99/55377, forinstance.

In another preferred embodiment of the invention, the interferon isInterferon-β (IFN-β), and more preferably IFN-β1a.

Osteopontin is preferably used simultaneously, sequentially, orseparately with the interferon.

In a preferred embodiment of the present invention, osteopontin is usedin an amount of about 0.0001 to 100 mg/kg of body weight, or about 0.01to 10 mg/kg of body weight or about 1 to 5 mg/kg of body weight or about2 mg/kg of body weight.

The invention further relates to the use of a nucleic acid molecule formanufacture of a medicament for the treatment and/or prevention of aneurologic disease, wherein the nucleic acid molecule comprises anucleic acid sequence encoding a polypeptide comprising an amino acidsequence selected from the group consisting of:

(a) A polypeptide comprising SEQ ID NO: 1;

(b) A polypeptide comprising amino acids 1 to 168 or 170 of SEQ ID NO:1;

(c) A polypeptide comprising amino acids 1 to 16 and 170 to 314 of SEQID NO: 1;

(d) A polypeptide comprising amino acids 170 to 314 of SEQ ID NO: 1;

(e) A polypeptide comprising SEQ ID NO: 2;

(f) A polypeptide comprising SEQ ID NO: 3;

(g) A mutein of any of (a) to (f), wherein the amino acid sequence hasat least 40% or 50% or 60% or 70% or 80% or 90% identity to at least oneof the sequences in (a) to (f);

(h) A mutein of any of (a) to (f) which is encoded by a DNA sequencewhich hybridizes to the complement of the native DNA sequence encodingany of (a) to (f) under moderately stringent conditions or under highlystringent conditions;

(i) A mutein of any of (a) to (f) wherein any changes in the amino acidsequence are conservative amino acid substitutions to the amino acidsequences in (a) to (f);

(j) an isoform, fused protein, functional derivative, active fraction orcircularly permutated derivative of any of (a) to (f).

The nucleic acid may e.g. be administered as a naked nucleic acidmolecule, e.g. by intramuscular injection.

It may further comprise vector sequences, such as viral sequence, usefulfor expression of the gene encoded by the nucleic acid molecule in thehuman body, preferably in the appropriate cells or tissues.

Therefore, in a preferred embodiment, the nucleic acid molecule furthercomprises an expression vector sequence. Expression vector sequences arewell known in the art, they comprise further elements serving forexpression of the gene of interest. They may comprise regulatorysequence, such as promoter and enhancer sequences, selection markersequences, origins of multiplication, and the like. A gene therapeuticapproach is thus used for treating and/or preventing the disease.Advantageously, the expression of osteopontin will then be in situ.

In a preferred embodiment, the expression vector is a lentiviral derivedvector. Lentiviral vectors have been shown to be very efficient in thetransfer of genes, in particular within the CNS. Other well establishedviral vectors, such as adenoviral derived vectors, may also be usedaccording to the invention.

A targeted vector may be used in order to enhance the passage ofosteopontin across the blood-brain barrier. Such vectors may target forexample the transferrin receptor or other endothelial transportmechanisms.

In a preferred embodiment of the invention, the expression vector may beadministered by intramuscular injection.

The use of a vector for inducing and/or enhancing the endogenousproduction of osteopontin in a cell normally silent for expression ofosteopontin, or which expresses amounts of osteopontin which are notsufficient, are also contemplated according to the invention. The vectormay comprise regulatory sequences functional in the cells desired toexpress osteopontin. Such regulatory sequences may be promoters orenhancers, for example. The regulatory sequence may then be introducedinto the appropriate locus of the genome by homologous recombination,thus operably linking the regulatory sequence with the gene, theexpression of which is required to be induced or enhanced. Thetechnology is usually referred to as “endogenous gene activation” (EGA),and it is described e.g. in WO 91/09955.

The invention further relates to the use of a cell that has beengenetically modified to produce osteopontin in the manufacture of amedicament for the treatment and/or prevention of neurologic diseases.

The invention further relates to a cell that has been geneticallymodified to produce osteopontin for manufacture of a medicament for thetreatment and/or prevention of neurologic diseases. Thus, a celltherapeutic approach may be used in order to deliver the drug to theappropriate parts of the human body.

The invention further relates to pharmaceutical compositions,particularly useful for prevention and/or treatment of neurologicdiseases, which comprise a therapeutically effective amount ofosteopontin and a therapeutically effective amount of an interferon,optionally further a therapeutically effective amount of animmunosuppressant.

The definition of “pharmaceutically acceptable” is meant to encompassany carrier, which does not interfere with effectiveness of thebiological activity of the active ingredient and that is not toxic tothe host to which it is administered. For example, for parenteraladministration, the active protein(s) may be formulated in a unit dosageform for injection in vehicles such as saline, dextrose solution, serumalbumin and Ringer's solution.

The active ingredients of the pharmaceutical composition according tothe invention can be administered to an individual in a variety of ways.The routes of administration include intradermal, transdermal (e.g. inslow release formulations), intramuscular, intraperitoneal, intravenous,subcutaneous, oral, epidural, topical, intrathecal, rectal, andintranasal routes. Any other therapeutically efficacious route ofadministration can be used, for example absorption through epithelial orendothelial tissues or by gene therapy wherein a DNA molecule encodingthe active agent is administered to the patient (e.g. via a vector),which causes the active agent to be expressed and secreted in vivo. Inaddition, the protein(s) according to the invention can be administeredtogether with other components of biologically active agents such aspharmaceutically acceptable surfactants, excipients, carriers, diluentsand vehicles.

For parenteral (e.g. intravenous, subcutaneous, intramuscular)administration, the active protein(s) can be formulated as a solution,suspension, emulsion or lyophilised powder in association with apharmaceutically acceptable parenteral vehicle (e.g. water, saline,dextrose solution) and additives that maintain isotonicity (e.g.mannitol) or chemical stability (e.g. preservatives and buffers). Theformulation is sterilized by commonly used techniques.

The bioavailability of the active protein(s) according to the inventioncan also be ameliorated by using conjugation procedures which increasethe half-life of the molecule in the human body, for example linking themolecule to polyethylenglycol, as described in the PCT PatentApplication WO 92/13095.

The therapeutically effective amounts of the active protein(s) will be afunction of many variables, including the type of protein, the affinityof the protein, any residual cytotoxic activity exhibited by theantagonists, the route of administration, the clinical condition of thepatient (including the desirability of maintaining a non-toxic level ofendogenous osteopontin activity).

A “therapeutically effective amount” is such that when administered, theosteopontin exerts a beneficial effect on the neurologic disease. Thedosage administered, as single or multiple doses, to an individual willvary depending upon a variety of factors, including osteopontinpharmacokinetic properties, the route of administration, patientconditions and characteristics (sex, age, body weight, health, size),extent of symptoms, concurrent treatments, frequency of treatment andthe effect desired.

As mentioned above, osteopontin can preferably be used in an amount ofabout 0.0001 to 10 mg/kg or about 0.01 to 5 mg/kg or body weight, orabout 0.01 to 5 mg/kg of body weight or about 0.1 to 3 mg/kg of bodyweight or about 1 to 2 mg/kg of body weight. Further preferred amountsof osteopontin are amounts of about 0.1 to 1000 μg/kg of body weight orabout 1 to 100 μg/kg of body weight or about 10 to 50 μg/kg of bodyweight

The route of administration, which is preferred according to theinvention is administration by subcutaneous route. Intramuscularadministration is further preferred according to the invention.

In further preferred embodiments, osteopontin is administered daily orevery other day.

The daily doses are usually given in divided doses or in sustainedrelease form effective to obtain the desired results. Second orsubsequent administrations can be performed at a dosage which is thesame, less than or greater than the initial or previous doseadministered to the individual. A second or subsequent administrationcan be administered during or prior to onset of the disease.

According to the invention, osteopontin can be administeredprophylactically or therapeutically to an individual prior to,simultaneously or sequentially with other therapeutic regimens or agents(e.g. multiple drug regimens), in a therapeutically effective amount, inparticular with an interferon. Active agents that are administeredsimultaneously with other therapeutic agents can be administered in thesame or different compositions.

The invention further relates to a method for treating a neurologicdisease comprising administering to a patient in need thereof aneffective amount of osteopontin, or of an agonist of osteopontinactivity, optionally together with a pharmaceutically acceptablecarrier.

A method for treating a neurologic disease comprising administering to apatient in need thereof an effective amount of osteopontin, or of anagonist of osteopontin activity, and an interferon, optionally togetherwith a pharmaceutically acceptable carrier, is also within the presentinvention.

All references cited herein, including journal articles or abstracts,published or unpublished U.S. or foreign patent application, issued U.S.or foreign patents or any other references, are entirely incorporated byreference herein, including all data, tables, figures and text presentedin the cited references. Additionally, the entire contents of thereferences cited within the references cited herein are also entirelyincorporated by reference.

Reference to known method steps, conventional methods steps, knownmethods or conventional methods is not any way an admission that anyaspect, description or embodiment of the present invention is disclosed,taught or suggested in the relevant art.

The foregoing description of the specific embodiments will so fullyreveal the general nature of the invention that others can, by applyingknowledge within the skill of the art (including the contents of thereferences cited herein), readily modify and/or adapt for variousapplication such specific embodiments, without undue experimentation,without departing from the general concept of the present invention.Therefore, such adaptations and modifications are intended to be withinthe meaning an range of equivalents of the disclosed embodiments, basedon the teaching and guidance presented herein. It is to be understoodthat the phraseology or terminology herein is for the purpose ofdescription and not of limitation, such that the terminology orphraseology of the present specification is to be interpreted by theskilled artisan in light of the teachings and guidance presented herein,in combination with the knowledge of one of ordinary skill in the art.

Having now described the invention, it will be more readily understoodby reference to the following examples that are provided by way ofillustration and are not intended to be limiting of the presentinvention.

EXAMPLES Example 1

Osteopontin is Differentially Expressed in in Vivo and in Vitro Modelsof Demyelinating Diseases

Methods

In Vitro Model Systems

The Oli-neu cell line has been established via immortalization ofoligodendroglial precursors with a replication-defective retrovirusencoding the t-neu oncogene, a constitutively active tyrosine kinase:this cell line was shown to be induced to differentiate in the presenceof 1 mM dibutyryl-cAMP in the culture medium (Jung et al., 1995). Thisprovided the possibility of studying oligodendrocytes as an isolatedcell type.

The morphology and antigenic characteristics of cells of the mouseoligodendrocyte cell line Oli-neu, derived from A2B5 mouseoligodendrocyte precursors, in the untreated condition and after 6 daysof pro-differentiating treatment with 1–5 mM dibutyryl-cAMP differssubstantially. Whereas untreated Oli-neu cells have a round shape andare mostly bipolar like oligodendrocyte precursor cells, cAMP treatedcells generate multiple processes, have a flat phenotype, and evenproduce flat, extended “sheath-like” structures

Additionally, an in vitro myelination assay using mixed corticalcultures can be used to enable visualization of functional myelin invitro. This system provides the possibility of studying howoligodendrocytes contact and myelinate axons in the presence of otherCNS cell types (Lubetzki et al., 1993) In this system, biologicalfactors can be tested, which might influence the proliferation ofoligodendrocyte precursors or act on the differentiation and survival ofoligodendrocytes, such as influencing the formation of real myelinsegments. The need to study the process of myelination in vitro has ledto the development of a range of assay types, including aggregatingbrain cell cultures (Matthieu et al., 1992), cerebellar slice cultures(Notterpek et al., 1993), and co-culturing systems (Shaw et al., 1996;Barres et al., 1993). These models have the advantage of permitting thestudy of oligodendrocyte behavior in conjunction with other cell typesand how these cells are stimulated to produce myelin. Demyelination canalso be provoked in such systems via specific insults, and the responseprocess of remyelination can also be studied.

In Vivo Model Systems

There exist a wide range of experimental in vivo and in vitro models formultiple sclerosis. Most of the in vivo models are related to theclassical animal model of MS, experimental allergic encephalomyelitis(EAE). There are many variations on this model, which has been adaptedfor use in a wide range of mammalian organisms, including the mouse,rat, and primate systems (reviewed in Petry et al., 2000). Additionally,methodologies have been formulated for “mimicking” the proposed viralcomponent of MS in animal models such as the encephalitogenic Theiler'smurine virus model of MS (Dal Canto et al., 1995).

Animal models for exclusively studying myelination in the CNS or PNS areless commonly used. It has proven useful to observe the process ofdevelopmental myelination in order to gain some insight into themechanisms underlying oligodendroglial or Schwann cell differentiation,migration, and proliferation, following the “recapitulation hypothesis”(Franklin and Hinks, 1999). However, in order to compare developmentalmyelination, which occurs while the CNS or PNS is still being formed,and remyelination, which occurs in an adult paradigm, it has beennecessary to formulate models that specifically address the process ofremyelination.

The Cuprizone Model

One of the most well known and widely used of the remyelination modelsis the Cuprizone model for remyelination in the mouse. This involvesoral administration of an organic compound, Cuprizone, a copper chelatorthat has been shown to be selectively toxic to oligodendrocytes (Morellet al., 1998).

Demyelination and remyelination occur in the corpus callosum ofCuprizone-treated mice. These pathological conditions can be visualizedby staining with anti-CNPase antibody or MBP antibody. Myelin is stainedwith Luxol Fast Blue-periodic acid Schiff (LFB-PAS). Remyelinatingoligodendrocyte precursors can be visualized using antibodies for PDGFαreceptor or NG2.

Administration of Cuprizone to mice over a period of 3–5 weeks resultsin extensive demyelination of the corpus callosum. Concomitant withdemyelination, synthesis of myelin-specific gene transcripts isupregulated after 3 weeks of Cuprizone administration (Morell et al.,1998).

Subsequent cessation of the Cuprizone regimen creates an environmentconducive to recovery, such that 6 weeks after ceasing Cuprizonefeeding, the mice exhibit extensive remyelination in the corpuscallosum. Thus, the Cuprizone model provides a complete in vivo paradigmwithin which to study aspects of demyelination and remyelination. Itsadvantages include the absence of T-cell infiltration into CNS tissue,enabling more exclusive study of myelination processes, as well as thereproducibility of results (Hiremath et al., 1998).

For Cuprizone treatment, C57BU/6 female mice (8 weeks old, 20±3 g) wereused in the study, which involved 6 groups, each containing 6 animals.

Group 1: control group fed with normal powdered chow;

Group 2: fed for 3 weeks on a powdered diet containing 0.2% Cuprizone(Cup3w);

Group 3: fed for 5 weeks on a powdered diet containing 0.2% Cuprizone(Cup5w);

Group 4: fed for 5 weeks on a powdered diet containing 0.2% Cuprizone,followed by a 1-week recovery period on a normal powdered diet (1wR);

Group 5: fed for 5 weeks on a powdered diet containing 0.2% Cuprizone,followed by a 3-week recovery period on a normal powdered diet (3wR);

Group 6: fed for 5 weeks on a powdered diet containing 0.2% Cuprizone,followed by a 6-week recovery period on a normal powdered diet (6wR).

Brains were collected from the animals in each group at the end of eachtreatment at fixed times. Mice were first anesthetized and perfused viathe left ventricle. Brains were collected and serial coronal sectionswere made at the level of corpus callosum-caudate putamen (striatum) andhippocampus. Brain tissue sections were embedded in paraffin forimmunohistochemistry and in situ hybridization.

Histological Tissue Preparation

Formalin was prepared by diluting 1 volume of formaldehyde (Fluka, 36%p.a.), and 1 volume of sterile PBS, with 8 volumes of sterile water. Asilicon tube adapted to a peristaltic pump and fitted with a 20G, 1⅕needle was filled with 10 ml of PBS. The tube was then filledcontinuously with 40 ml of formalin, with care being taken to preventair bubble formation.

Animals were anesthetized with sodium pentobarbital (Sanofi®), diluted1:1 with sterile PBS to a concentration of 3 mg/100 ml, prior tointracardial perfusion with fixative to permit subsequent histologicalanalysis of organs and tissues. Each mouse received an intraperitonealinjection of 0.05 ml (0.75 mg/kg). Once animals were drowsy, their limbswere fixed with pins (25G ⅝ needles) through the skin onto a Styrofoamboard. The abdomen of each animal was cleansed with ethanol and anincision made with sterile scissors in the skin at the level of theexterno. The abdomen was then further cut to the right and to the leftside. The externo was lifted with a pair of forceps and the diaphragmwas opened through a diagonal incision, and a bilateral incisionperpendicular to the rips was made to expose the thoracic cavity withthe beating heart in the middle. The heart was held with forceps and theright atrium immediately cut to allow venous bleeding. The circulationof 10 ml PBS was permitted, followed by 40 ml formalin in the case ofeach mouse. The brain and spinal cord of each animal were carefullydissected out and placed in 10 ml formalin solution in a 50 ml Falcon®tube for 2 hours. The formalin solution was then changed by 10 mlsterile PBS and the material left at +4° C. overnight. The PBS solutionwas then changed again and the material was left at +4° C. for a fewhours. The brain hemispheres and spinal cord were cut into approximately0.5 cm slices and placed into plastic basquets compatible with theinclusion machine. Embedding of the brain and spinal cord in paraffinwas done using an automatic Tissue Tek Vacuum Infiltration ProcessorE150/E300 (Miles Inc. Diagnostics) according to the program describedbelow:

30 minutes in 50% ethanol

60 minutes in 70% ethanol

60 minutes in 70% ethanol

60 minutes in 80% ethanol

90 minutes in 80% ethanol

30 minutes in 96% ethanol

90 minutes in 96% ethanol

120 minutes in 96% ethanol

30 minutes in 100% xylene

60 minutes in 100% xylene

Four 60 minute incubations in paraffin (Histosec, Merck 11609); laststage is for embedding.

All solutions were kept at 40° C. with the paraffin at 65° C. Once thetissue sections were ready, the brain and spinal cord sections wereplaced in the desired orientation on plastic chambers for paraffin blockinclusion. The paraffin liquid was poured and allowed to cool quickly at0° C. on a cool plate. Paraffin blocks were processed in a microtome forsectioning (5–10 μm). Sections were then mounted onto silane-treatedglass slides (SuperFrost-Plus™, Menzel cat. no. 041300). Followingmounting, slides were stored in a dust-free environment.

Cell Culture

Oli-neu: Mouse oligodendrocyte cell line (Oli-neu) cells were enrichedvia centrifugation and resuspended in Sato's medium (Trotter et al.,1989). Cells were cultured in 75-mL flasks at 37° C. and 5% CO₂controlled conditions. Differentiation was performed with 1 mM dbcAMPadded directly to cell culture medium. RNA was extracted using theTrizol Method (see below).

RNA Isolation

Total RNA was isolated from Oli-neu cells, cuprizone-treated mouse brainsections and mouse post-natal whole brains at different developmentalstages using the Tri-ZOL® extraction protocol (Life Technologies AG,Basel, Switzerland). Poly(A)⁺ RNA was prepared from total RNA samplesusing Qiagen OLIGOTEX™ columns (QIAGEN Inc., 28159 Stanford Avenue,Valencia, Calif. 91355, USA).

DGE Analysis Using cDNA Microarrays

Microarray experiments were done at Incyte Genomics (Incyte GenomicsInc., 3160, Porter Drive, Palo Alto, Calif. 94304, USA). DGE analysiswas performed using Incyte's Mouse GEM™ 1 gene expression microarray(http://www.incyte.com/reagents/gem/products.shtml).

The Incyte chips used in these assays were loaded with cDNA moleculescorresponding to 8734 genes, both known and unknown (EST sequences).Incyte's technology permitted micro samples of each of these genes to bespotted on a single array. Each cDNA molecule corresponding to a knowngene or EST was 500–5000 bp in length. The Incyte specifications gave adetectable dynamic range of 2 to 2,000 pg for individual mRNA in asample. The quantity of RNA required for each array experiment was 600ng of poly(A)⁺ RNA. Stated levels of detectable differential expressionwere given as ratios larger than 1.75.

Signal Normalization and Expression Level Determination

Ratios computed from the 2 fluorescence intensities provide quantitativemeasurement of the relative gene expression level in the 2 cell samplesbeing analyzed. The ratios assigned to each gene are computed based onnormalized expression levels. A normalization factor is computed bydividing the total expression of the second sample (P₂) by the totalexpression of the first sample (P₁). This factor is then applied to theexpression level of each gene in P₂. Once this normalization step hasbeen applied, the gene ratios are computed according to the followingrule:

Let E₁ be the expression level of a given gene in sample 1 and let E₂ bethe normalized expression level of the same gene in sample 2; if E₂>E₁then ratio=E₂/E₁, otherwise ratio=−E₁/E₂.

Since sample hybridization is performed simultaneously in competition,the Incyte chip technology is more precise in determining relativeexpression changes and becomes less reliable for the measurement ofabsolute expression levels. Nevertheless, it is possible to use theseexpression level values for comparing pairs of sample RNA populationsthat were not actually physically compared on a chip. Such in silicocomparisons are less reliable but they can provide additionalinformation on mechanisms that might apply to the systems being assayed.

Results

Models Used for Analysis of Differential Osteopontin Expression

Table IV shows the models, which were used for extraction of mRNA andchip hybridization (DGE analysis), as described above.

TABLE IV Models used in DGE analysis Models Treatments Controls 1. Invitro Oli-neu cells + Oli-neu cells (untreated) oligodendrocytedibutyryl-cAMP differentiation (6 hours) model Oli-neu cells + Oli-neucells (untreated) dibutyryl-cAMP (6 days) 2. In vivo Adult frontalbrain + Untreated adult Cuprizone Cuprizone (3 weeks) frontal braindemyelination/re- Adult frontal brain + Untreated adult myelinationmodel Cuprizone( 5 weeks) frontal brain Adult frontal brain + Adultfrontal brain + Cuprizone (3 weeks) Cuprizone (5 weeks) 3. DevelopmentalMouse post-natal day 10 Mouse post-natal day 2 myelination (P10)cerebellum (P2) cerebellum

Positive control for DGE: Regulation of Myelin-specific genes.

As positive control, it was first tested if differential regulation ofmyelin-specific genes could be shown using DGE.

Table V shows the regulation observed for myelin-specific genes presenton the Incyte microarrays. Differential expression values for each geneare reported from both the 3-week and 5-week time points of cuprizonetreatment. This data is a positive control for verifying chipreliability. Since the regulation of myelin structural genes under ourexperimental conditions is well characterized, the observed expressionof these genes measured on the chips could be used to indicate a)accuracy of the technology and b) reproducibility of our models.

TABLE V In vivo regulation of myelin-specific genes in microarray assayson in vivo myelination models. Accession Cup Cup P Gene Name Number 3 w5 w 2/10* Myelin basic protein AA059540 113.6 11.3 +7.9 Myelin vesicularprotein/myelin and AA519027 33.5 11.7 0 lymphocyte protein (MVP/MAL)Cyclic nucleotide W63987 22.9 11.1 +2.9 phosphodiesterase 1 (CNPase)*Postnatal cerebellum day 2/10

The above table shows how some myelin-specific genes were regulated inthe microarray assays performed on RNA from different in vivo modelsused to study demyelination, remyelination and developmentalmyelination. The changes in expression of these myelin-specific genesindicate how the process of myelination can be studied at the level oftranscriptional regulation using microarrays.

After 3 weeks of cuprizone administration, the demyelinating effect ofthe treatment can be visualized in specific areas of the mouse brain.Therefore, at 3 weeks it was expected to observe the downmodulation ofvarious genes associated with myelin synthesis and/or myelinmaintenance. The downregulation of myelin-specific genes as observed viamicroarray serves as a confirmation of the accuracy and reliability ofthe experimental system. The data presented in Table V shows that themRNA levels for MBP, downregulated 13.6-fold, and cyclicnucleotide-phosphodiesterase 1 (CNPase), downregulated 2.9-fold, werereduced at 3 weeks of cuprizone treatment compared to controls. However,the RNA levels for both these genes had returned to 1.3- and 1.1-foldbelow normal levels respectively after 5 weeks of cuprizone treatment,indicating that the biological system was attempting to establishremyelination by boosting synthesis of the structural myelin proteins.

Differential Regulation of Osteopontin:

On the chip, Osteopontin was upregulated at 3w (+2.2) and 5w (+2.8)Cuprizone.

Example 2

Confirmation of Differential Gene Expression of Osteopontin by Real-TimeQuantitative Reverse Transcriptase (RT)-PCR Assay (TaqMan®)

Methods

cDNA Template Generation

The cDNA templates for TaqMan® analysis were generated from total RNAsamples via reverse-transcription (RT) using the TaqMan® reversetranscription reagents (P/N N808–0234). All RT reactions were performedin a 100-μl volume containing: 10 μl TaqMan RT buffer, 22 μl 25 mM MgCl₂solution (5.5 mM), 20 μl deoxyNTPs mixture (500 μM of each dNTP), 5 μlrandom hexamers (2.5 μM), 2 μl RNase inhibitor (0.4 U/μl), 2.5 μl.MultiScribe™ Reverse Transcriptase (1.25 U/μl) and 38.5 μl RNA sample (1μg total) in RNase-free H₂O. Reactions were performed on an EppendorfMasterCycler at 25° C. for 10 min (incubation step), 48° C. for 30 min(reverse transcription), and 95° C. for 5 min (inactivation step). Allsynthesized cDNAs were stored at −20° C. in 20 μl volumes.

Primer Design and Verification

SYBR Green Real Time PCR forward and reverse primers for all confirmedgenes and GAPDH (house keeping control) were designed using the PrimerExpress™ software from PE Biosystems according to the publishedsequences and ordered at 0.02 μM concentration from Interactiva(Interactiva: The Virtual Laboratory, Sedanstrasse 10, D-89077 Ulm). Thespecificity and optimal primer concentrations were tested for eachprimer set. Potential genomic DNA contamination was monitored byperforming PCR reactions on negative control cDNA samples that had beensubjected to reverse transcription reactions in the absence of the RTenzyme. Absence of non-specific amplification was confirmed by analyzingthe PCR products via agarose gel electrophoresis on 3.5% MetaPhor gelsor pre-cast NuSieve® 4% gels.

Table VI indicates the sequences of the gene-specific primers designedfor performing TaqMan® analysis to confirm differential expression ofgenes shown to be differentially regulated on microarrays. The names ofthe genes corresponding to each primer pair and the GenBank accessionnumber of the sequence used to design each primer with thePrimerExpress™ software are also included.

TABLE VI Primers used for RT-PCR analysis Acces. TaqMan ® SEQ ID GeneName Number OLIGO NAME TaqMan ® OLIGO SEQUENCE NO Secreted AAOsteopontin-166F AGCCTGCACCCAGATCCTATAG 4 phosphoprotein 108928Osteopontin-235R GCGCAAGGAGATTCTGCTTCT 5 1 (osteopontin)

TaqMan Reactions

SYBR Green Real-Time PCR was performed with 5 μl/well of RT-products(0.5 ng total RNA), 25 μl/well of SYBR Green PCR master mix, (AppliedBiosystems, CA, USA) with AmpErase Uracil N-Glycosylase (UNG) (0.5Unit/well) and 20 μl of primers (300 nM). PCR was performed at 50° C.for 2 min (for AmpErase UNG incubation to eliminate any potentialcarryover by removing uracil incorporated into the PCR productsgenerated from previous TaqMan runs), 95° C. for 10 min (for AmpliTaqGold activation). Then samples were run for 40 cycles at 95° C. for 15sec, 60° C. for 1 min on the ABI PRISM® 7700 Sequence Detection. System.The reverse-transcribed cDNA samples were thus amplified and their C_(T)(threshold cycle) values were determined. All C_(T) values werenormalized to the housekeeping gene GAPDH. Where possible, samples wererun in duplicate or triplicate to gauge the reproducibility of theresult. A single specific DNA band for all confirmed genes and GAPDH wasobserved upon electrophoretic analysis.

Calculation of Gene Regulation Via Cycle Threshold (C_(T))

The principle of real-time detection using the SYBR Green PCR master mixis based upon the direct detection of PCR product by measuring theincrease in fluorescence created by the binding of SYBR Green dye todouble-stranded DNA. This permits quantification of the relativeincrease in a gene-specific amplification product based on PCR growthcurves.

Measurement of specific cDNA species relative to a control sample isperformed by quantification of cDNA converted from a messenger RNAcorresponding to the specific gene relative to a calibrator sampleserving as a physiological reference. The calibration is provided by asample from a control or untreated condition. Relative quantification ofthe cDNA species is completed via normalization to an endogenous control(in this case, GAPDH) to account for any variability in the initialconcentration and quality of the total RNA used to generate templatecDNAs and in conversion efficiency of reverse transcription reactions.Calculation of relative quantitation values was performed by taking themean C_(T) value for the replicate reactions run for each sample,calculating the difference (ΔC_(T)) in mean C_(T) between target samplesand the endogenous controls, subtracting the mean C_(T) of thecalibrator for the target from the ΔC_(T) of that target (ΔΔC_(T)) andfinally expressing the relative quantification value for the target as2^(−ΔΔCt) to gauge the extent of the up- or down-regulation in geneexpression.

Normalization of Fluorescence Signals in TaqMan® Reactions

SYBR Green-dsDNA complex fluorescence signals are normalized to thepassive reference or negative control reactions containing no templateDNA. Normalization was performed via division of the emission intensityof SYBR Green-dsDNA complex in the experimental reaction by the emissionintensity of the passive reference. This yields the R_(n) (normalizedreporter) ratio for the reaction:

-   -   R_(n) ⁺=R_(n) value of a reaction containing all components        including template DNA    -   R_(n) ⁻=R_(n) value of an unreacted sample (no template DNA)    -   ΔR_(n)=(R_(n) ⁺)−(R_(n) ⁻) where:    -   R_(n) ⁺=(emission intensity of SYBR Green-dsDNA complex)/PCR        with template (emission intensity of passive reference)    -   R_(n) ⁻=(emission intensity of SYBR Green-dsDNA complex)/No        template (emission intensity of passive reference)

Calculation of Fold Regulation from Cycle Threshold (C_(T)) Values

ΔR_(n) represents the magnitude of the signal generated by the given setof PCR conditions for a specific reaction. The cycle threshold parameterconstitutes a measurement of the relative increase in amplification ofthe gene-specific product, which represents relative abundance of aspecific transcript in an experimental cDNA population. It is fixed asthe cycle point at which a statistically significant increase in ΔR_(n)is first detected. The threshold is defined as the average standarddeviation of R_(n) for the early cycles, multiplied by an adjustablefactor. The cycle threshold parameter is used for quantitation ofdifferential gene expression. Specific values are calculated for eachgene-specific growth curve based on the point or cycle at which anincrease above background fluorescence intensity is detected.

All calculation of relative quantitation values was performed by takingthe mean C_(T) value for the replicate reactions run for each sample,calculating the difference (ΔC_(T)) in mean C_(T) between target samplesand the endogenous controls and subtracting the mean C_(T) of thecalibrator for the target from the ΔC_(T) of that target (ΔΔC_(T)).Finally, the relative quantification value for the target was expressedas 2^(−ΔΔCt) to gauge the extent of up- or down-regulation in geneexpression.

Results

Real-time quantitative reverse transcriptase (RT)-PCR (TaqMan) providesa sensitive and reliable approach to confirming and elucidating changesin gene expression. The TaqMan sequence detector (ABI PRISM® 7700Sequence Detection System, Applied Biosystems, Foster City, Calif.)integrates a PCR-based assay with hardware/software instrumentation toprovide a system for high-throughput quantification of nucleic acidsequences. This combines thermal cycling, fluorescence detection, andapplication-specific software to permit the cycle-by-cycle detection ofthe increase in the amount of a specific PCR product.

Expression of several highly regulated genes pinpointed via microarrayanalysis was verified using the TaqMan® platform. In each case, as faras possible, a time course for each model system being used wasincluded. This permitted more data to be gathered regarding how specificgenes behaved during a complete process:

Changes in gene expression could be quantitated via TaqMan® via directdetection of an increase in the PCR product via measurement offluorescence created by the binding of SYBR Green dye to double-strandedDNA, represented by amplification products specific to the gene beingassayed. Measurement of specific cDNA species relative to a controlsample is performed by quantification of cDNA converted from a messengerRNA corresponding to the specific gene relative to a calibrator sampleserving as a physiological reference. Calibration is provided by asample from a control or untreated condition. Relative quantification ofthe cDNA species is calculated with normalization to GAPDH to accountfor any variability in initial concentration and quality of the totalRNA used to generate template cDNAs and in the conversion efficiency ofreverse transcription reactions.

Expression of secreted phosphoprotein 1 (osteopontin) gene was analyzedin a time course study spanning the demyelination/remyelination paradigmassociated with the cuprizone model.

Results of TaqMan experiments for osteopontin expression in thecuprizone remyelination model are shown in FIG. 1(A). The mRNA levels ofosteopontin were found to be upregulated 18 fold in mouse frontal brainsafter 3 weeks of cuprizone administration (3w. Cup.), and 25-fold after5 weeks of treatment (5w. Cup.).

Osteopontin expression was downregulated after 1, 3 and 6 weeks ofregeneration further to 5 weeks of cuprizone treatment (5w. cup.+1w. 3w.and 6w.). These findings indicate an important role of osteopontin inthe demyelinating and remyelination phase of the model, sinceremyelination starts when demyelination is still ongoing.

FIG. 1(B) shows the results of osteopontin expression levels indeveloping Cerebellum. Osteopontin mRNA is transiently upregulatedduring early postnatal development, days C4 to C8, which is the timeperiod of initiation of myelination in the cerebellum.

Microarray results had indicated upregulation of osteopontin in mousefrontal brains during cuprizone treatment. This analysis extends theprofile of osteopontin expression to include both the demyelinating andremyelinating phases of cuprizone treatment, and shows that theosteopontin expression profile peaks during the demyelinating phase ofcuprizone treatment, and during the recovery period returns to nearbaseline levels

The results are shown in Table VII below.

The results of TaqMan® analysis of osteopontin expression confirmed itsupregulation in the brains of mice fed with cuprizone for 3 and 5 weeks.

TABLE VII TaqMan ® analysis of osteopontin regulation in the Cuprizonemodel Tissue type Experiment Expression levels regulation Frontal brainCup. control 1.00 Control level Frontal brain Cup. control −1.32 downFrontal brain 3 w. Cup. 17.51 up Frontal brain 3 w. Cup. 23.43 upFrontal brain 5 w. Cup. 20.25 up Frontal brain 5 w. Cup. 23.43 upFrontal brain 5 w. Cup. + 1 w. R. 1.79 up Frontal brain 5 w. Cup. + 1 w.R. 3.32 up Frontal brain 5 w. Cup. + 3 w. R. 2.95 up Frontal brain 5 w.Cup. + 3 w. R. 4.56 up Frontal brain 5 w. Cup. + 5 w. R. −1.16 downFrontal brain 5 w. Cup. + 5 w. R. 1.04 Control level Frontal brain 5 w.Cup. + 5 w. R. 1.07 Control level

Example 3

Confirmation of Differential Osteopontin Expression by Northern Blot

Methods

Blot Preparation

For specific genes, tissue specificity of expression was assayed usingmouse Multi-Tissue Northern blots (Clontech Labs, 1020 East MeadowCircle, Palo Alto, Calif.). These contained 2 μg of poly(A)⁺ RNA perlane from different tissues of the adult mouse. Separate blots wereprepared for analysis of differential gene expression in both in vitroand in vivo situations. RNA isolated from the brains of cuprizonetreated mice at 3 weeks, 5 weeks and the 1, 3 and 6-week time pointsduring the recovery process (up to 6 weeks) was used on one set ofblots. Whole brain RNA from different postnatal day stages was used on asecond set. Finally, a time-course series of RNAs was prepared fromOli-neu cells grown in culture and treated for different lengths of timewith dibutyryl-cAMP. This RNA was used to prepare a third set of blots.New blots were used with each gene-specific probe to ensure maximaldetection efficiency and minimize variations in results due to unevenstripping after hybridization. All blots were hybridized twice, firstwith a probe against the gene of interest and then, following stripping,with a probe against mouse glyceraldehyde-3-phosphate (mGAPDH) tocontrol for variations in RNA loading.

RNA (10 μg/well) was loaded onto a 1.2% denaturing agarose gelcontaining formaldehyde and 5×MOPS (209.27 g3-(N-morpholino)-propanesulfonic acid, 20.5 g sodium acetate, 50 mL 0.5M EDTA pH 8.0 in 5 L with sterile H₂O, to pH. 7.0 with 12 M NaOH). EachRNA sample was mixed with 2 μl ethidium bromide (0.01 mg/ml), 2 μl5×3-(N-morpholino)propanesulfonic acid (MOPS), 3.5 μl 37% formaldehydeand 10 μl formamide. Samples were then heated at 65° C. for 10 minutesand quick-chilled on ice. Two microliters RNA loading buffer (50%glycerol, 1 mM EDTA, 0.4% bromophenol blue and 0.4% xylene cyanol dye)was added to each sample immediately prior to loading on the gel.

Each gel run was ˜3 hours in a 1×MOPS running buffer (1L=330 mL 37%formaldehyde, 400 mL 5×MOPS, 270 mL DEPC-treated H₂O) at 5 V cm⁻¹ (gellength). This was followed by an overnight RNA transfer to a positivelycharged nylon membrane (Hybond™-N, Amersham Life Sciences, AmershamPlace, Little Chalfont, Buckinghamshire, England HP7 9NA) using SSCsolution as described (Terry Brown, Unit 4.9, Current Protocols, 1993[ed. F. M. Ausubel, R. Brent, R. E. Kingston, D. D. Moore. J. G.Seidman, J. A. Smith, and K. Struhl]). The RNA transfer efficiency waschecked by viewing the membrane and flattened gel under UV light. RNAswere cross-linked to the membrane via Stratalinker (Stratagene, USA).Blots were stored between sheets of Whatman 3 MM filter paper at roomtemperature prior to hybridization.

Probe Preparation

Radioactive ³²P-labeled probes were prepared using gel-purifiedrestriction fragments of cDNA clones (˜500>800 bp in length)corresponding to genes of interest. DNA fragments were randomly labeledto a specific activity >10⁹ cpm ml⁻¹ with ³²P-dCTP using the HighPrime™labeling system (Roche Diagnostics AG, Industriestraβe 7, 6343 Rotkreuz,Switzerland). Unincorporated ³²P-dCTP was removed via gravity-basedelution of the probe mixture through a Pharmacia NAP™-5 columncontaining Sephadex® G-25 Medium (DNA Grade in distilled watercontaining 0.15% Kathon® CG/ICP Biocide®).

Hybridization and Signal Detection

Probe hybridization was performed using ExpressHyb™ (Clontech Labs, 1020East Meadow Circle, Palo Alto, Calif.) according to manufacturerspecifications. Blots were exposed following hybridization to Hyperfilm™MP (Amersham Pharmacia Biotech, England) at −80° C. in autoradiographycassettes. Stripping the probe following exposure was performed byincubating the blot for 10 minutes in sterile H₂O/0.5% SDS solution at90–100° C. and then allowing the blot to cool for 10 minutes. Strippedmembranes were sealed in plastic and stored at −20° C. until needed forreprobing.

Results

Northern blot analysis has previously been employed as a secondaryconfirmation technique in large-scale differential gene expressionstudies (Chang et al, 2000). Its sensitivity and accuracy permitsanalysis of not only tissue specificity of expression for a given geneof interest but also the magnitude of differential regulation betweenexperimental and control conditions. This makes it a reliable method forconfirming DGE results obtained via microarray analysis. Also, Northernblots provide information relating to transcript sizes and possiblealternative splice isoforms corresponding to the gene of interest.

Custom Northern blots were prepared using RNA isolated from the brainsof cuprizone-treated and control mice. These were probed withradioactively labeled DNA fragments from clones sent to us by IncyteGenomics. The ability of Northern blots to reproduce the resultsobserved via TaqMan® analysis of gene expression was verified using aradioactively labeled probe against mouse osteopontin hybridized to ablot of RNAs isolated from the brains of mice treated with cuprizone. Inthis manner, it was possible to compare the Northern blot analysis tothe TaqMan® analysis of the expression of osteopontin in the cuprizonemodel.

FIG. 3 shows the open reading frame for mouse osteopontin inserted intothe pT7T3D-Pac vector as ordered from Incyte Genomics. The grey regionis the coding sequence and the arrow represents the complete cDNA forosteopontin. The clone insert was flanked by EcoRI and NotI restrictionsites. To make a probe for use in Northern blotting in order to analyzetissue expression of this gene, an 893-bp fragment was cut from theclone using the HincII and StyI restriction enzymes. This fragment wasgel-purified and labeled for use as a probe.

The expression of mouse osteopontin was ascertained via Northern blotanalysis using a custom blot prepared with RNAs from the brains of micefrom each stage in the cuprizone model, including recovery and untreatedcontrols. The blot was probed first with a radioactively labeledfragment of the mouse osteopontin cDNA, stripped following exposure, andthen reprobed with a radioactively labeled fragment of mouse GAPDH. Thiswas used as a positive control to account for differences in observedexpression levels based on variations in the overall amounts of RNA ineach lane on the blot.

The expression of osteopontin in the brains of cuprizone-treated micereaches a peak at 3 and 5 weeks of Cuprizone feeding, with slightlyhigher expression at 5 weeks. During the recovery phase, levels ofosteopontin mRNA diminish relatively rapidly, with an appreciablereduction in expression 1 week after the cessation of cuprizone feeding.The levels of osteopontin mRNA return to approximately normal levelsafter 6 weeks recovery. This is qualitatively comparable to the resultsobtained in TaqMan® analysis of osteopontin expression in the cuprizonemodel (see FIG. 1A).

Example 4

Regulation of Osteopontin in Oli-Neu Cells

Osteopontin expression in oligodendrocytes (oli-neu) treated with CAMPwas measured by TaqMan analysis. The results are shown in FIG. 4.Columns 1 to 4 show the results obtained in the oligodendrocytes. Ascompared to control (value=1), 6 h of treatment with cAMP (col. 1) ledto an upregulation of osteopontin mRNA. After 2 d of cAMP treatment(col. 2), a 12 times upregulation was measured. Prolonged treatment for6 to 10 d (col. 3,4) led to lower levels of osteopontin mRNA. Acomparison to the regulation of osteopontin mRNA in the cuprizone model(col. 5, 6) showed that the upregulation of osteopontin after 3 and 5weeks of curpizone in frontal brain was comparable to upregulation inoligodendrocytes after 2 d of cAMP treatment

Example 5

Expression of Osteopontin in Oligodendrocytes

Method

Oli-neu cells were transiently transfected following the calciumphosphate precipitation method. Briefly, oli-neu cells from theexponential growth phase were seeded (10e5/ml) into 6-well plate the daybefore the transfection is performed. A solution of 100 μI of 250 mMCaCI2 was mixed with 5 μg of plasmid DNA. An equal volume (100 μI) of2×HEPES solution (140 mM NaCI, 50 mM HEPES pH 7.05) supplemented withphosphate from 300 mM stock solution of Na2HPO4 and NaH2PO4 at pH 7.05was added to the Ca/DNA solution. Exactly one minute later, the mixturewas gently added to the culture plate and incubated for 4 hours at 37°C. in CO₂ incubator. After this time, the medium was replaced with freshmedium and the cells were then incubated for 24–72 hours beforeharvesting and analyzing by Western blotting.

Results

Different mouse osteopontin constructs, in pDEST12.2 vector(pDEST12.2-osteopontin-EGFP, pDEST12.2osteopontin-His6,pDEST12.2-osteopontin, see FIGS. 4 to 7, and pCIE-EGFP as controlplasmid) were transfected in oli-neu cells. The protein was produced andsecreted by the cells as detected by specific commercial antibodies (R&DSystems, AF808). The EGFP tagged construct made the monitoring of thetransfection easier and 24 hours after the transfection, a specificchange of cell morphology (increase in oligodendrocyte processes) couldbe detected in comparison with the pCIEGFP control (not shown), whichindicated that osteopontin drives the mouse oligodendrocyte cell lineoli-neu toward a more mature morphological phenotype. The morphologypresented by osteopontin transfected oli-neu cells was very similar tothe morphology of a myelinating oligodendrocyte.

These results demonstrate that the expression of osteopontin inoligodendrocytes is beneficial to drive these cells towards myelination,and therefore indicate a beneficial effect of osteopontin in diseaseslinked to oligodendrocyte dysfunction.

Example 6

Expression of Osteopontin Protein in Specific Regions of the Brain inthe Cuprizone Model

Osteopontin immunohistochemistry was performed on various time pointsduring de- and remyelination in the Cuprizone model. Strong signals werefound in the demyelinated corpus callosum and striatum bundles at 5weeks of cuprizone treatment, a time point associated with prominentmicroglia recruitment to the sites of demyelination. In order tovisualize the activated microglia cells, a CD68 staining at consecutivesections was carried out, and the similar expression patterns suggestmicroglia expression of osteopontin.

Interestingly, osteopontin was also found in cells lining the anteriorventricles. This region was described as the adult subventricular zonebearing multipotent stem cells for the production of neurons, astrocytesand oligodendrocytes. Double stainings with NG2, PSA-NCAM, PDGFαreceptor will be performed in order to determine the oligodendrocyteprecursor cells expressing osteopontin.

Example 7

Effects of Osteopontin Protein on Oligodendrocyte Proliferation

A murine primary oligodendrocyte (oligodendroglial) cell lineimmortalized with the t-neu oncogene (“oli-neu” cell line) was used inthis experiment. The establishment and properties of the oli-neu cellline as well as the culturing conditions are described in Jung et al.(1995).

The aim of this study was the measurement of the effects of OPN onoligodendrocyte proliferation in a oli-neu proliferation assay. Cellswere plated subconfluently. They were starved for 24 hours in insulinfree medium before treatment with either control or recombinantproteins. Cell numbers were quantitated with Alamar blue, giving afluorescent read out. Calculations for potentiation were based on thecomparison to the IGF1 (control) standard curve. The calculations forinhibition of proliferation were based on the comparison to the dbcAMPstandard curve.

Material

Equipments and Softwares

Wallac Victor 2 multilabel counter (excitation at 530–560 nm, emissionat 590 nm)

Graph Pad Prism software

Reagents

oli-neu cell line (Eur J Neuro 7:125–1265 (1995))

Alamar blue (BioSourceIntl. Inc., Camarillo, Calif. 93012)

Components for Sato medium were as follows: Product Supplier Stock μlper 500 ml DMEM Seromed F0435  500 ml Transferrin Sigma T-2252  100mg/ml (1 mg in 10 ml PBS)   50 Sodium Selenite Sigma S-9133   1 mg/2.56ml PBS   50 Insulin Sigma I-1882   10 mg/ml (100 mg/10 ml PBS)  500Putrescine Sigma P-7505 80.5 mg/ml (PBS)  500 Progesterone Sigma P-01300.62 mg/ml (EtOH)   50 TIT Sigma T-5516  1.7 mg/ml (1/3 HCl 1 N + 2/3EtOH  100 (Triiodothyronine) L-Thyroxine Sigma T-0397 2.88 mg/ml + 1drop NaOH 1 N  100 L-Glutamine Gibco 25030-024  200 mM  5000 GentamycinGibco 15750-037   50 mg/ml  250 Sodium Gibco 25080-052 7.50% 13000Bicarbonate Horse Serum  5000

BioCoat flat bottom plate, coated with poly D lysine (356461) fromBecton Dickinson); R3-IGF1 (I1146 from Sigma); DbcAMP (D-0627 fromSigma)

Method

Cultivation of Cells for in Vitro Bioassay

Oli-neu cells are adherent cells growing on Poly-L-Lysine substrateCells were plated on BioCoatTM poly-lysine pre-coated 96 well plates.The cells were split 2–3×/week. In order to split, they were firstwashed with PBS and then detached with PBS plus 1 mMEDTA. Cells weregrown in a humidified 10% CO2 incubator.

The freezing medium used was Sato Medium with 20% FCS and 10% DMSO. Inthis experiment, oli-neu cells of no higher than passage 16 were used.Cells were used at a final concentration of 4000 cells per well in 96well plate after 24 starvation in Sato medium minus insulin.

Alamar Blue Staining

After 48 hrs in CO2 incubator, 10 μl of Alamar Blue stock was added tothe wells and incubated for additional 2.5 hours. The fluorescence wasmonitored at 530–560 nm excitation and 590 nm emission wave length.Plates could be read up to 4 hours and up to 1 million relativefluorescence units.

Experimental Design

As controls, 100 ng/ml R3-IGF-1 (positive control), or 1 mM dbcAMP(negative control), or medium without insulin, or 100 nM of boiled OPN,were used. Experimental samples were 1 nM, 10 pM, 0.1 pM, 0.01 pM or 100nM of recombinant osteopontin. Controls and experimental samples werediluted to the desired concentrations with a final volume of 50 μI inSato medium minus insulin and added to wells. Oli-neu cells were grownin insulin-free medium for 24 hours, and then treated with controls orexperimental samples for 48 hours. Detached oli-neu cells that werefreshly starved for 24 hours in medium minus insulin, were harvestedfrom the growth flask with PBS plus 1 mM EDTA. The cells were preparedat 300,000 cells per ml and added 50 μl per well. Then, the cells wereincubated 48 hours at 37° C. in a humidified CO2 incubator. 10 μl alamarblue were added and the cells were returned to incubator for 2.5 hours.Then, 70 μl from each well were transferred to black 96 well plates andthe fluorescence was measured immediately.

The proliferation of undifferentiated oli-neu cells was measured after24 hours in response to different amounts of osteopontin, which wasproduced using the insect cells (BacOPN), or a mammalian expressionsystem (HEK-OPN). The growth rate was quantified by measuring thecellular metabolic activity with a fluorometric/colorimetric growthindicator, Alamar Blue. This agent contains an oxidation-reductionindicator that shows both fluorescence and changes its color in responseto chemical reduction of growth medium resulting from cell growth. Theagent and assay used are described in Ahmed et al. (1994) and the U.S.Pat. No. 5,501,959.

Results

The results are shown in FIGS. 8 to 10.

A dose response was observed with recombinant osteopontin, bothbaculovirus expressed and HEK cell expressed. Degeneration of theprotein by boiling destroyed the biological activity, as expected.Addition of baculovirus expressed osteopontin (BacOPN) and HEK cellexpressed OPN (HEK OPN) resulted in a dose-dependent increase of cellproliferation (FIG. 8) with a IC50 for BacOPn of 3.7 nM and 0.05 nM forHekOPN (FIG. 9). In addition, an N-terminal OPN construct correspondingto amino acids 1 to 168 of OPN isoform a (see FIG. 2, N-term. OPN-a) wasexpressed in insect cells. The purified protein was tested in theproliferation assay in comparison to the full-length protein. Thetruncated protein was active (10 nM, 100 nM), see FIG. 10.

Example 8

Effects of Osteopontin on the Expression of Myelination Markers in MixedCortical Cultures

Mixed cortical cultures, grown on coverslips, were treated with Bac OPN(100 nM) for 12 days from DIV (days in vitro) 5–17. At 17 days in vitrothe cultures were fixed and stained with an anti-MBP antibody. Theresults show that BacOPN coverslips had more highly branched MBPpositive oligodendrocytes than controls (FIG. 11). In addition, whereasin control cultures (FIG. 11A) no myelinating oligodendrocytes wereseen, OPN treated cultures (FIGS. B, C and D) are rich inoligodendrocytes, which wrap around axons and form myelin segments andinternodes. (FIGS. 11B to D). Counting of segment clusters revealed thatwhile no segments could be observed in the control, three different OPNtreated samples showed 16, 22, and 18 segment clusters. These resultsindicate that the treatment of cortical mixed cells with osteopontinleads to a differentiated phenotype of oligodendrocytes, which ischaracteristic for myelinating oligodendrocytes.

Example 9

Effects of Osteopontin on the Expression of MBP in Mixed CorticalCultures as Measured by MBP ELISA

MBP ELISA Was used in order to monitor MBP protein increase and thusmyelination in OPN and LIF treated mixed cortical cultures.

Primary Cultures

The source of the material was embryonic mouse brain tissue fromembryos, isolated from pregnant NMR1 female mice at 16 days post-coitum.Embryos were dissected according to the protocol of Lubetzki et al.,cortices were dissociated via trypsin digestion and the dissociatedcells (including neurons, astrocytes, oligodendrocytes, microglia andneuronal precursors) were seeded at 1*10⁵ cells per well ontopoly-L-lysine pre-coated 96-well culture plates (at a 50-μl initialvolume) for each well.

Recombinant Protein Treatment

Treatments were performed using recombinant proteins (positive control,recombinant mouse leukemia inhibitory factor (LIF) purchased from AMRADLaboratories, at concentrations of 1 μg/ml, 100 ng/ml, and 10 ng/ml;mouse baculovirus-produced full-length osteopontin at concentrations of100 nM, 10 nM, and 10 pM). All proteins were diluted in culture mediumto the appropriate concentrations from stock material, prior to additionto cells in vitro. Cultures were allowed to grow for 5 days in vitro andthen were treated for 17 days subsequently. Medium was changed every 3days.

Microwell Plate Protocol for Sample Harvesting

Cells were lysed and samples harvested after 17 days in vitro (DIV17).Cell lysis was performed using triple detergent buffer.

Triple detergent buffer Final concentration   50 ml Tris pH 8.01 M  50mM 8.77 g NaCl 150 mM   2 ml NaN₃ (10%) 0.02%   5 ml SDS 20%  0.1%   10ml NP40   1%   5 g sodium deoxycholate  0.5%

A single protease inhibitors tablet (Roche no. 1836170) was added to 10ml of triple detergent buffer solution prior to use.

Medium was removed from mixed cortical culture samples that had beenseeded in 96-well pre-coated plates. Cells were washed gently twice with50 μl of 1×PBS and then 50 μl of triple detergent buffer was added toeach well. All microwell plates containing the lysed samples were thenstored at −20° C. prior to analysis.

BCA Protein Assay

The Pierce BCA Protein Assay is a detergent-compatible formulation basedon bicinchoninic acid (BCA) for the colorimetric detection andquantification of total protein. This method combines the well-knownreduction of Cu⁺² to Cu⁺¹ by protein in an alkaline medium with thehighly sensitive and selective colorimetric detection of the curprouscation (Cu⁺¹) using a unique reagent containing bicinchoninic acid.

The purple-colored reaction product of this assay is formed by thechelation of two molecules of BCA with one cuprous ion. This watersoluble complex exhibits a strong absorbance at 562 nm that is linearwith increasing protein concentrations over a broad working range of 20μg/ml to 2000 μg/ml. The BCA method is not a true end-point method—thefinal color continues to develop but, following incubation, the rate ofcolor development is slowed sufficiently to allow large numbers ofsamples to be done in a single run. The macromolecular structure ofprotein, the number of peptide bonds and the presence of four aminoacids (cysteine, cysteine, tryptophan and tyrosine) are reported to beresponsible for color formation with BCA.

Microwell Plate Protocol for Determination of Total Protein Content

25 μl of each standard (BSA concentration: 2000 μg/ml, 1500 μg/ml, 1000μg/ml, 750 μg/ml, 500 μg/ml, 250 μg/ml, 125 μg/ml, 25 μg/ml) and sampleswere added into the appropriate microwell plate wells. 25 μl of thediluent (triple detergent buffer) was used for the blank wells (workingrange 20–2000 μg/ml).

200 μl of working reagent (mixture of 50 parts of BCA Reagent A with 1part of BCA Reagent B), was added to each well. Plate well was shakenfor 30 seconds and incubated at 37° C. for 30 minutes. After incubationthe absorbance values were measured at 570 nm.

MBP Sandwich ELISA

96-well flat-bottomed sterile microplates (Costar) were incubatedovernight at +4° C. with the anti-MBP antibody (Chemicon, MAB5274)diluted 1:5000 in 1×PBS. 50 μl of the dilute antibody solution was addedto each well.

The next day, the antibody solution was removed from all wells in theplates and a blocking step was performed using 50 μl of a 1% BSAsolution in 1×PBS for each well. Blocking was performed for 1 hour atambient temperature. Plates were robotically washed 3 times followingthe blocking step using PBS/Tween.

Incubation was performed after the addition of serial dilutions of theMBP peptide standard or samples in 1% BSA/PBS to the microwell plates.The MBP peptide 100 ng/ml stock solution was diluted 2 in 2. Thedilutions used here were determined after calculation of total proteincontent using the results of the BCA Protein Assay. They were asfollows:

100 μg; 50 μg; 25 μg; 12.5 μg; 6.2 μg; 3.1 μg.

Following incubation with the MBP standard and protein samples, plateswere washed 3 times again in 1% BSA/PBS.

A second incubation was performed using a polyclonal anti-MBP antibody(Zymed 10–0038, 1:300) diluted in 1% BA/PBS. Plates were incubated for 2hours at ambient temperature. Following this incubation, plates wereagain washed 3 times as above.

Incubation with goat anti-rabbit biotin (Vector BA-1000, 1:10,000),added in 50-μl volumes to all wells after dilution in 1% BSA/PBS, wasperformed for 1 hour at ambient temperature. Plates were again washedfollowing the incubation as indicated above.

The final incubation was performed with 50 μl of streptavidin-conjugatedhorse radish peroxidase (strep-HRP) (Amersham RPN 1051, 1:8000) dilutedin 1×PBS being added to each well. Plates were incubated for 1 hour atambient temperature.

Following the washing step, the reaction was revealed usingorthophenylenediamine dihydrochloride (OPD) (Sigma, solution prepared byadding 1 tablet to a 20-ml volume of water). This reaction was blockedvia addition of 3 M HCl or 30% H₂SO₄. The optical density was measuredusing a multi-scan fluoroplate reader (Labsystems Multiskan EX) at 492nm.

Results

As shown in FIG. 12, MBP protein levels were increased 3 fold in bacOPN(10 nM) treated cultures at DIV 17 compared to control cultures. Thisobservation supports the previous results showing a positive effect ofbaculovirus expressed OPN on oligodendrocyte precursor proliferation andmyelination.

Example 10

Effect of Osteopontin on CG4 Proliferation

The CG4 cell line is a rat immortalized oligodendrocyte cell line, whichwas spontaneously obtained from primary A2B5 oligodendrocyte precursors.CG4 cells are a commonly used cell line to study oligodendrocytedifferentiation or survival. The CG4 cell line has the followingadvantages:

-   -   High proliferative rate like oligodendrocyte progenitors        (O2A-like) (GD3, A2B5-positive cells);    -   Low cost maintenance in conditioned medium (with effective        growth-factor concentrations) obtained from B104 rat        neuroblastoma cell line (Louis J. C. et al. 1992) obtained from        ATCC.    -   Defined medium (without FBS) can be used (supplemented with        FGF2+PDGF) instead of B104 conditioned medium for proliferation        during short periods;    -   Differentiation into oligodendrocytes (O4,GaIC-positive) can be        triggered with a defined medium;    -   Differentiation into astrocytes (GFAP-positive) can be triggered        in the presence of FBS.

Passage number 35 of the CG4 cells was used test an effect of two OPNproteins (expressed in E. coli or insect cells) on proliferation. R&DSystem E. coli produced osteopontin (Cat.441-OP) was used for thisassay, which was then in vitro phosphorylated with protein kinase 2 (GSTfused) in a 60 μl volume as follows:

Kinase buffer 6x: Sample Buffer 2x pH6 Hepes 50 mM Tris-Cl 0.125 MgCl₂10 mM Glycerol 20% DTT 1 mM DTT 0.2 M Sodium Vanadate 0.2 mM BromophenolBlue 0.02% Beta glycerolphosphate 25 mM

ATP Mix (60 μM)

30 μl ATP at 600 μM

5 μl of ³²pATP

265 μl H₂O₂

In order to start the reaction ATP mix was added and the incubation wasperformed at 30° C. for 1 hour. After 90 minutes incubation at 30° C.(with agitation), 100 μl Glutathione Sepharose beads (Pharmacia) wereadded to the reaction mix that was previously washed in PBS in order toeliminate protein kinase. Then, the mix was incubated for one hour atroom temperature with gentle agitation. The suspension was centrifugedat 500 g for 5 minutes to sediment the beads. Then, the supernatant wasdialysed overnight supernatant at 4° C. against PBS. The protein wasquantified by BCA (Pierce).

Kinase Reaction:

10 μl Casein Kinase at 0.05 μg/μl

10 μl E. coli OPN at 0.5 μg/μl

20 μl 50 mM Tris-HCL ph 8

10 μl kinase buffer 6×

10 μl ATP mix

Proliferation Assay

Bad OPN and in vitro phosphorylated OPN proteins were tested at 10 pM,10 nM and 100 nM concentrations on proliferation of CG4 cells. As areadout BrdU (Amersham) was used as described in Avellana et al. 1996.The cells were cultured in 70% N1 defined medium (DMEM containing 4.5g'l glucose, 2 mM glutamine, 100 U/ml penicillin. 100 μg/ml streptomycinand 1 mM sodium pyruvate and supplemented with 5 μg/ml transferrin, 100mM putrescine, 30 nM sodium selenite and 10 ng/ml biotin) and 30% B104conditioned medium (N1 without Biotin) (Louis J. C. et al. 1992). Theassay was performed in poly-ornithine (100 μg/ml) treated 24 well platesseeded with 3×10⁴ cell/per well. 10 nM BrdU was added the at the sametime and cells were incubated for 18 hours. After fixation,immunocytochemistry was performed with an anti-BrdU antibody to detectcell divisions. Cells were also stained with Hoechst 44432 staining(Sigma) to allow total cell numbers counts. Images were acquired andanalyzed using the Leica QWin Image Analysis System.

Results

The results are depicted in FIG. 13.

Baculovirus expressed osteopontin leads to increased proliferation ofCG4 cells. The most pronounced effect could be observed at aconcentration of 10 nM OPN, although 100 nM of OPN led to proliferationas well. In vitro phosphorylated, E. coli expressed OPN lead to minorproliferation of CG4 cells.

Analysis of the morphology of OPN treated versus non-treated CG4 cellsrevealed that while in the control, no differentiation could beobserved, OPN treated CG4 cells were differentiated in that most of thecells developed processes. While differentiation was more pronouncedusing baculovirus expressed OPN, E. coli expressed, in vitrophosphorylated OPN lead to CG4 cell differentiation as well (not shown).

Example 11

Effect of Osteopontin on MOG-induced Experimental AutoimmuneEncephalomyelitis (EAE) in Mice

Purpose of the Study

Osteopontin (OPN; AS900011) is a cytokine with pleiotropic functionsincluding those in adhesion, migration, differentiation, survival andcytokine secretion of various cell types. OPN was identified in adifferential gene expression (DGE) approach with the aim of detectinggenes that could regulate remyelination and oligodendrocyte function(see Example 1). Treatment of oligodendrocyte precursors withrecombinant baculovirus expressed OPN (AS900011) increased proliferationin a dose dependent manner (IC₅₀: 3.7 pM, see example 7). In addition,AS900011 showed an effect on the differentiation of CG4 cell line andprimary neurospheres (see example 8). OPN is expressed in thedemyelinated corpus callosum brain region of mice treated withCuprizone, where expression was strongest in microglial cells (seeexample 1). In addition, OPN expression was observed in thesub-ventricular zone (SVZ), which has been suggested to generateoligodendrocyte precursors that participate in remyelination (seeexample 4). It is hypothesized that OPN, a cytokine with variousimmuno-regulatory properties, may also play a role as a modulator ofneuronal and glial function.

The purpose of this study was to test the therapeutic effect of OPN inthe model of MOG-induced EAE in mice.

Test Method

The method of induction of EAE used for this study has been adapted fromthe protocol published by Sahrbacher et al. (1998). Protection ofanimals used in the experiment is in accordance with Directive86/609/EEC, enforced by the Italian D.L. No. 116 of Jan. 27, 1992.Physical facilities and equipment for accommodation and care of animalsare in accordance with the provisions of EEC Council Directive 86/609.The Institute is fully authorized by Competent Veterinary HealthAuthorities. All parts of this protocol concerning animal care have beenapproved by the official Veterinarian. This protocol is authorized byItalian Ministry of Health (Decree No. 51/99-B).

Test System

Species, strain, substrain and sex:

C57 BL/6JICO female mice from the IFFA CREDO (Saint Germain surl'Arbresle, France) colony was supplied by Charles River Italia (Calco,Lecco, Italy).

Justification for the selection of the test system:

The C57 BL/6JICO mouse was chosen as an experimental model; thisselected strain has documented susceptibility to EAE.

Supplier:

Charles River Italia S.p.A.

Via Indipendenza, 11

23885-Calco (Lecco)

Acclimation:

At least 5 days before the study is initiated. In this period theanimals will be observed daily to ascertain their fitness for the study.

Age and body weight (at randomization):

About 8 week old; 18–22 g

Housing:

10 animals/cage in air-conditioned rooms.

Temperature: 22° C.±2

Relative humidity: 55%±10

Air changes: about 15–20/hour filtered on HEPA 99.99%.

Light: 12 hour cycle (7 a.m. –7 p.m.)

Cage: Makrolon® cage 42.5×26.6×15 h each fitted with a stainless steelcover-feed rack. A grill is inserted on the cage bottom. The waste thatdrops through the grill onto the cage bottom will be periodicallydisposed of.

Animal Identification:

By an ear tag. Cage card will give experiment number, dosage, group anddate of compound administration.

Diet:

GLP 4RF25 top certificate pelleted diet produced by Charles RiverItalia's feed licensee Mucedola S.r.I., Settimo Milanese. To facilitatenourishment of sick animals from day 7 wet pellets are placed every dayon the cage bottom. The Producer supplies a certificate of analysis fornutrients and contaminants, the levels of which are within the limitsproposed by EPA-TSCA (44FR:44053–44093, Jul. 26, 1979). RBM has theanimal food reanalyzed at least twice a year for bacterialcontamination. The diet is available “ad libitum” to the animals.

Water:

From the municipal main watering system. Water is filtered anddistributed “ad libitum” to the animals by an automatic valve system.Plastic bottles are used in addition to the automatic watering system.Periodically drinking water is analyzed for microbiologic count, heavymetals, other contaminants (e.g. solvents, pesticides) and otherchemical and physical characteristics. The acceptance limits of qualityof the drinking water are those defined in the EEC Directive 801778.

Contaminants that might interfere with the objectives of the study arenot expected to be present in diet or drinking water.

Test Substances:

Murine, 6 his-tagged Osteopontin (AS900011) and mIFNβ

Immunization Procedure:

Mice were immunized (day=0) by injecting s.c. in the left flank 0.2 mlof an emulsion composed of 200 μg MOG₃₅₋₅₅ peptide (Neosystem,Strasbourg, France) in Complete Freund's Adjuvant (CFA, Difco, Detroit,U.S.A.) containing 0.5 mg of Mycobacterium tuberculosis. Immediatelyafter, they received an i.p. injection of 500 ng pertussis toxin (ListBiological Lab., Campbell, Calif., U.S.A.) dissolved in 400 μl of buffer(0.5 M NaCl, 0.017% Triton X-100, 0.015 M Tris, pH=7.5). On day 2 theanimals were given a second i.p. injection of 500 ng pertussis toxin. Onday 7, the mice received a second dose of 200 μg of MOG₃₅₋₅₅ peptide inCFA injected s.c. in the right flank. Starting approximately from day8–10, this procedure results in a gradually progressing paralysis,arising from the tail and ascending up to the forelimbs.

Study Design:

The study involved 7 groups of 15 animals each. All the groups wereimmunized with MOG₃₅₋₅₅ peptide in CFA and pertussis toxin, according tothe Immunization protocol and treated as follows:

Group 1: positive control group dosed with OPN vehicle alone (PBS+0.1%BSA) by s.c. route.

Group 2: positive control group dosed with mIFNβ vehicle alone (PBS) bys.c. route.

Group 3: dosed with 1 μg/kg s.c. of Osteopontin (AS900011)

Group 4: dosed with 10 μg/kg s.c of Osteopontin (AS900011)

Group 5: dosed with 100 μg/kg s.c. of Osteopontin (AS900011)

Group 6: dosed with 100 μg/kg s.c. of Osteopontin (AS900011) plus 20,000U/mouse s.c. of mIFNβ

Group 7: dosed with 20,000 U/mouse s.c. of mIFNβ

The number of animals per group is the minimum number allowing anaccurate assessment of observed pharmacological effects.

Vehicle:

PBS plus 0.1% BSA will be used to dilute Osteopontin to the appropriateconcentration. PBS will be used to dilute mIFNβ to the appropriateconcentration.

Administration Route:

Osteopontin (AS900011) at the dose of 1, 10 and 100 μg/kg wasadministered s.c. in a volume of 10 ml/kg. mIFNβ at the dose of 20,000U/mouse will be administered s.c. in a volume of 200 μl/mouse. Group 1will be dosed s.c. with PBS plus 0.1% BSA in a volume of 10 ml/kg andgroup 2 will be dosed s.c. with 200 μl/PBS/mouse.

Duration of Treatment:

The treatment of groups of this study was started for each animal at theappearance of a clinical score ≧1 and will then be continued for 35consecutive days.

Form of Administration:

The compound and mIFNβ were administered as solutions in the appropriatevehicle. Respective formulates will be prepared in accordance with theSponsor's instructions.

Clinical Observations:

Starting from day 7 post-immunization the animals were individuallyexamined for the presence of paralysis by means of a clinical score asfollows:

0=no sign of disease

0.5=partial tail paralysis

1=tail paralysis

1.5=tail paralysis+partial unilateral hindlimb paralysis

2=tail paralysis+hindlimb weakness or partial hindlimb paralysis

2.5=tail paralysis+partial hindlimb paralysis (lowered pelvi)

3=tail paralysis+complete hindlimb paralysis

3.5=tail paralysis+complete hindlimb paralysis+incontinence

4=tail paralysis+hindlimb paralysis+weakness or partial paralysis offorelimbs

5=moribund or dead

Observation of the animals took place in a quiet room. Clinical signswere monitored daily in each group of treatment in a blind fashion by atechnician who is unaware of treatments.

Body weight of the animals were monitored daily.

Animals considered to be in pain distress or in moribund condition willbe examined by the staff veterinarian or authorized personnel and, ifnecessary, humanely sacrificed to minimize undue pain or suffering.

Blood Sampling:

Twenty four hours after the last treatment, blood samples will becollected (under pentobarbital anaesthesia) from each animal. Serum willbe separated by routine procedure and serum samples will be kept storedat −20° C. Frozen sera will be then shipped to SPRI for the relativedeterminations of compound serum concentration.

Histopathological Examinations:

At the end of treatment, the animals, under pentobarbital anaesthesia,will be perfused-fixed with 4% formaldehyde via the left ventricle.Then, their spinal cords will carefully be dissected out and fixed informalin. Spinal cord slices will be embedded in paraffin blocks.Sectioning and staining with hematoxylin and eosin for inflammation, andwith Kluver-PAS (Luxol fast blue plus Periodic Acid Schiff staining) forthe detection of demyelination, will be performed.

Data Evaluation:

Results of clinical examinations are expressed as the mean (±SEM) scorewithin each group. The effects of the test substances will be comparedwith that of the vehicle-treated positive control group. Differences ofclinical score values among groups will be analysed by Kruskal-Wallistest followed, in case of significance, by the pairwise Wilcoxon test,at each measurement time. Body weight data will be evaluated by one-wayANOVA followed, in case of significance, by Tukey test. The S- Plus®software will be used.

Results:

The results of this study are shown in FIGS. 14 to 16.

Histological analysis of the perivascular inflammatory infiltratedrevealed that there was a trend towards a lower amount of perivascularinfiltrates in OPN treated animals, especially at the lowestadministered amount of 1 μg/kg. The combination of OPN and IFNβ, whichis a compound known to be active in treatment of multiple sclerosis, wasmore efficacious than administration of OPN or IFN alone, respectively(FIG. 14).

Next, the percentage of demyelinated areas was measured (FIG. 15).Again, in animals treated with OPN, a trend towards less demyelinatedareas could be observed. The combination of IFN and OPN lead to a highlysignificant reduction of demyelination, which was even much lower thanthe extent of demyelination that was observed with IFN alone (FIG. 15).

FIG. 16 summarizes the clinical scores observed at the end of thetreatment, the inflammatory infiltrations and the demyelination measuredin this study. Although the clinical scores observed in OPN treated micewere not significantly lower than the control, the combination of OPNand IFN led to a pronounced effect on the clinical scores, which was aslow as with the positive control, interferon-beta. This observation isin agreement with the measurement of the inflammatory infiltrates andthe extent of demyelination. Both parameters were significantly reducedafter administration of OPN and IFNβ (FIG. 16).

In summary, the following results were obtained in this study:

Osteopontin (AS900011) tested alone at the doses of 1, 10 and 100 mg/kgs.c. did not reduce perivascular infiltrations and demyelination withstatistical significance. The treatment with mIFNbeta (20,000 U/mouses.c.) induced a reduction in perivascular infiltrations (55%) anddemyelination (53%). When mIFNbeta at the same dose was combined withAS900011 at the dose of 100 mg/kg s.c., a significant and markedreduction in inflammatory infiltrations (71%) and demyelination (81%)was observed.

Histological data correlated with clinical scores observed at day 35(end of treatment), when animals were sacrificed and spinal cordcollected for histological analysis. Osteopontin (AS900011) tested aloneat the doses of 1, 10 and 100 mg/kg s.c. did not significantly reducedisease severity. The treatment with mIFNbeta (20,000 U/mouse s.c.)significantly reduced disease severity. When mIFNbeta at the same dosewas combined with AS900011 at the dose of 100 mg/kg s.c, a statisticallysignificant decrease of clinical signs was observed.

These data suggest that the combined osteopontin and mIFNbeta treatmentis effective in reducing both clinical and pathological effects in themouse EAE model, and may therefore be an efficient treatment of multiplesclerosis.

Example 12

Protective Effect of Osteopontin on Neuropathy Induced by Sciatic NerveCrush in Mice

Abbreviations

CMAP: compound muscle action potential

EMG: electromyography

IGF-1: insulin-like growth factor

SC: subcutaneous

s.e.m.: standard error of the mean

vs: versus

Introduction

Neuropathies are usually selective as to the type of PNS neuroneaffected (e.g. sensory versus autonomic) and indeed also to the subtypeof neurons (small versus large). Axotomy of peripheral nerves is themost commonly used animal model for appraising the neuroprotectiveeffects of neurotrophic factors. Traumatic nerve injury, plexus lesionsand root lesions are a serious complication of accidents. In addition,pressure on peripheral nerve that can cause myelin damage frequentlyseen in disorders such as carpal tunnel syndrome or is associated withspinal column orthopedic complications. Axotomy produces phenomena, likecell death, reduced axonal conduction velocity, and alteredneurotransmitter levels in damaged neurons. Crush lesions allow forregeneration, an additional process of interest in relation toneuropathic states (McMahon S. and Priestley J. V. 1995).

A fundamental question in cellular neurobiology is the regulation ofnerve regeneration after injury or disease. Functional nerveregeneration requires not only axonal sprouting and elongation, but alsonew myelin synthesis. Remyelination is necessary for the restoration ofnormal nerve conduction and for protection of axons from newneurodegenerative immunologic attacks. The primary goal of research inneurodegenerative disorders is ultimately to develop interventions whichprevent neuronal death, maintain neuronal phenotype and repair neuronaland myelin damage. Many studies have been devoted to the unraveling ofmolecular and cellular mechanisms responsible for the completeregeneration of axotomized spinal motor neurons (Fawcett et al., 1990;Funakoshi et al., 1993). Injury-induced expression of neurotrophicfactors and corresponding receptors may play an important role in theability of nerve regeneration. Previous studies have shown a significantimprovement of nerve regeneration with various peptides and nonpeptidescompounds like insulin-like growth factor (IGF-1), ACTH (Lewis et al.,1993; Strand et al., 1980), testosterone (Jones, 1993), SR57746A(Fournier et al., 1993) and 4-Methylcatechol (Kaechi K et al. 1993,1995; Hanaoka Y et al. 1992).

The present study was carried out to evaluate nerve regeneration in micetreated with osteopontin at different doses. In this model a positiveeffect of OPN on neuronal and axonal (sensory and motor neurons)survival and regeneration, on myelination or macrophage inflammationcould lead to a restoration of motor function. The regeneration may bemeasured according to the restoration of sensorimotor functions andmorphological studies. Therefore in the present workelectrophysiological recordings and histomorphometric analysis wereperformed in parallel.

Materials and Methods

Animals

Eightyfour 8 weeks-old females C57bI/6 RJ mice (Elevage Janvier, LeGenest-St-Isle, France) were used. They were divided into 7 groups(n=12): (a) vehicle sham operated group; (b) vehicle nerve crushoperated group; (c) nerve crush/osteopontine (1 μg/kg); (d) nervecrush/osteopontin (10 μg/kg); (e) nerve crush/osteopontin (100 μg/kg);(f) nerve crush/4-methylcatechol (10 μg/kg); (g) nerve crush/denaturatedosteopontin (100 μg/kg).

They were group-housed (5 animals per cage) and maintained in anincubator with controlled temperature (21–22° C.) and a reversedlight-dark cycle (12 h/12 h) with food and water available ad libitum.All experiments were carried out in accordance with institutionalguidelines.

Lesion of the Sciatic Nerve

The animals were anaesthetized with IP injection of 60 mg/kg ketaminechlorhydrate (Imalgene 500®, Rhône Mérieux, Lyon, France). The rightsciatic nerve was surgically exposed at mid thigh level and crushed at 5mm proximal to the trifurcation of the sciatic nerve. The nerve wascrushed twice for 30 s with a haemostatic forceps (width 1.5 mm; Koenig;Strasbourg; France) with a 90 degree rotation between each crush.

Planning of Experiments and Pharmacological Treatment

Electromyographical (EMG) testings were performed once before thesurgery day (baseline) and each week during 3 weeks following theoperation.

The day of nerve crush surgery was considered as day (D) 0. No test wasperformed during the 4 days following the crush.

Body weight and survival rate were recorded every day.

From the day of nerve injury to the end of the study, osteopontin anddenaturated osteopontin were administered daily by SC route whereasdaily injection of 4-methylcatechol was perform in IP.

At the 4^(th) week, 4 animals per group were sacrificed and sciaticnerve was dissected to perform morphological analysis.

Electrophysiological Recording

Electrophysiological recordings were performed using a Neuromatic 2000Melectromyograph (EMG) (Dantec, Les Ulis, France). Mice wereanaesthetized by intraperitoneal injection of 100 mg/kg ketaminechlorhydrate (Imalgene 500®, Rhône Mérieux, Lyon, France). The normalbody temperature was maintained at 30° C. with a heating lamp andcontrolled by a contact thermometer (Quick, Bioblock Scientific,Illkirch, France) placed on the tail.

Compound muscle action potential (CMAP) was measured in thegastrocnemius muscle after single 0.2 stimulation of the sciatic nerveat a supramaximal intensity (12.8 mA). The amplitude (mV), the latency(ms) and the duration (time needed for a depolarization and arepolarization session) of the action potential were measured. Theamplitude is indicative of the number of active motor units, while thedistal latency indirectly reflects motor nerve conduction andneuromuscular transmission velocities.

Morphometric Analysis

Morphometric analysis was performed 3 weeks after the nerve crush. Fourrandomly selected animals per groups were used for this analysis. Theywere anesthetized with IP injection of 100 mg/kg Imalgene 500®. A 5 mmsegment of sciatic nerve was excised for histology. The tissue was fixedovernight with a 4% aqueous solution glutaraldehyde (Sigma, L'Isled'Abeau-Chesnes, France) in phosphate buffer solution (pH=7.4) andmaintained in 30% sucrose at +4° C. until use. The nerve was fixed in 2%osmium tetroxide (Sigma, L'Isle d'Abeau-Chesnes, France) in phosphatebuffer for 2 h and dehydrated in serial alcohol solutions and embeddedin Epon. Embedded tissues were then placed at +70° C. during 3 days forpolymerisation. Transverse sections of 1.5 μm were made with a microtomeand stained of 1% of toluidine blue (Sigma, L'Isle d'Abeau-Chesnes,France) for 2 min and dehydrated and mounted in Eukitt. Twenty sectionsper sample were observed using an optical microscope (Nikon, Tokyo,Japan) and morphometric analysis was performed on 6 randomized slicesper nerve sample, with a semi-automated digital image analysis software(Biocom, France). Two fields per slice were studied. The followingparameters were calculated: the percentage of degenerate fibers (perfield) and total number of fibers.

Data Analysis

Global analysis of the data was performed using one factor or repeatedmeasure analysis of variance (anova) and one way anova, andnon-parametric tests (mann whitney test). dunnett's test was usedfurther when appropriate. The level of significance was set at p<0.05.The results were expressed as mean±standard error of the mean (s.e.m.).

Results

All the animals survived after the nerve crush procedures. A mice (nervecrush/vehicle n^(°)2) died on day 7 and 2 (vehicle sham operated n^(°)3and N^(°)6) on day 14, as a consequence of anesthesia during the EMGevaluation.

Animal Weight

As illustrated in FIG. 17, a significant intergroup was noted in thebody weight evolution throughout the study [F (6, 132)=1.93 and p<0.001;repeated measures ANOVA].

All different groups displayed an increase of body weight throughout thestudy.

Electrophysiological Measurements

Amplitude of the Compound Muscular Action Potential (FIG. 18):

There was a significant intergroup difference in amplitude of the CMAPthroughout the study [F (6, 18)=49.185 and p<0.001; repeated measureANOVA] (FIG. 19).

After the nerve injury, all animals submitted to nerve crush displayed asignificant decrease of CMAP amplitude in comparison with sham operatedgroup (p<0.001; Dunnett's test).

Moreover, on D 7 and D 14, CMAP amplitude of mice treated withosteopontin at 100 μg/kg or 4-methylcatechol at 10 μg/kg, weresignificantly higher than the nerve crush/vehicle one (p<0.05; Dunnett'stest).

No significant difference was noted between nerve crush/vehicle groupand nerve crush/D-osteopontin 100 μg/kg.

Latency of the Compound Muscular Action Potential (FIG. 19):

As illustrated in FIG. 20, a significant intergroup difference was foundin the CMAP latency [F (6, 18)=2.521 and p<0.001; repeated measuresANOVA]. On D 21, nerve crush groups presented an increased CMAP latencyin comparison with sham operated group (p<0.001; Dunnett's test).Moreover, osteopontin treatment at 10 and 100 μg/kg showed a significanteffect, indeed latency of these groups was significantly smaller thanthat of nerve crush/vehicle one (p=0.017; Dunnett's test).

There was no significant difference between the nerve crush/vehicle andnerve crush/D-osteopontin 100 μg/kg groups.

Duration of the Compound Muscular Action Potential (FIG. 20):

There was a significant intergroup difference in the CMAP durationthroughout the study [F (6, 18)=25.15 and p<0.001; repeated measuresANOVA] (FIG. 20).

Since D 7, a significant increase of CMAP duration was observed in nervecrush groups (sham operated group vs nerve crush groups: p<0.001;Dunnett's test). Moreover, at D 7 nerve crush/osteopontin 100 μg/kgdisplayed a duration significantly shorter than that of nervecrush/vehicle group (p<0.001; Dunnett's test).

On D 14 and D 21, three groups presented a significant decreasedduration in comparison with the nerve crush/vehicle group: (a) nervecrush/osteopontin 10 μg/kg; (b) nerve crush/osteopontin 100 μg/kg; (c)nerve crush/4-methylcatechol 10 μg/kg.

Furthermore, no significant difference was observed between the nervecrush/vehicle and nerve crush/D-osteopontin 100 μg/kg groups.

Morphometric Analysis

Percentage of Degenerate Fibers (FIG. 21):

Statistical analysis revealed a significant intergroup difference inpercentage of degenerate fibers per field (p<0.001; one way ANOVA) (FIG.22). All nerve crush groups displayed a significant increased percentageof degenerate fibers (p<0.001, Dunnett's test). Moreover, nervecrush/treated mice presented a percentage significantly lower than thatof nerve crush/vehicle group (p<0.001; Dunnett's test). Moreover, theD-osteopontin (100 μg/kg) treated group displayed an higher percentageof degenerated fibers than the osteopontin-treated groups (p<0.001;Dunnett's test).

Total Number of Fibers (FIG. 22):

Sections were observed using an optical microscope and morphometricanalysis was performed with the aid of the Visiolab 2000 software(Biocom, Paris, France). Five sections per animal, 2 fields per sectionwere analyzed. Only the functional myelinated fibers were recorded bythe computer (all the degenerated fibers meaning with a degeneration themyelin sheath are not recorded).

CONCLUSIONS

The nerve crush model a very dramatic model of peripheral neuropathy.Immediately after the nerve crush most of the big diameter fibers arelost, due to the mechanical injury, leading to the strong decrease inthe CMAP amplitude. The CMAP latency is not immediately affected butshows an increase at 21 days due to additional degeneration of smalldiameter fibers by secondary, immune mediated degeneration (macrophages,granulocytes). The CMAP duration is increased at day 7, peaks at day 14and returns to levels at day 21 which are comparable to the 7 daystimepoint. This is due to the fact that at 21 days, crush lesions allowfor regeneration, an additional process of interest in relation toneuropathic states. This axonal sprouting/regeneration was also evidentin control groups at the three weeks timepoint.

Osteopontin showed a protective effect in the nerve crush model in mice.Sensorimotor functions were significantly restored at 7, 14 and 21 dayspost injury in a dose dependent manner and morphological studiesperformed at 21 days post crush show a significant decrease in thepercentage of degenerating fibers and a increase in total fiber number.OPN is as effective as the control molecule used in this study,4-methylcatechol and heat inactivated, degenerated OPN protein does notshow any significant effect on functional or histological parameters.This positive effect on functional and histological recovery may be dueto OPN effects on:

-   -   direct protection of fibers from secondary immune mediated        degeneration;    -   accelerated remyelination and protection of axons;    -   accelerated regeneration/sprouting of damaged axons;    -   increased myelin debris clean up by macrophages.

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1. A method of treating a neurologic disease, comprising administeringto a patient in need thereof a medicament comprising osteopontin, or anagonist of osteopontin activity, optionally together with apharmaceutically acceptable carrier.
 2. The method according to claim 1,wherein the neurologic disease is selected from the group consisting oftraumatic nerve injury, stroke, demyelinating diseases of the central orthe peripheral nervous system, neuropathies and neurodegenerativediseases.
 3. The method according to claim 2, wherein the demyelinatingdisease is multiple sclerosis (MS).
 4. The method of claim 2, whereinthe neurodegenerative disease is selected from Alzheimer's disease,Parkinson's disease, Huntington's disease and amyotrophic lateralsclerosis (ALS).
 5. The method according to claim 1, wherein theneurologic disease is caused by a congenital metabolic disorder.
 6. Themethod according to claim 1, wherein the neurologic disease is aperipheral neuropathy.
 7. The method according to claim 6, wherein theneurologic disease is diabetic neuropathy.
 8. The method according toclaim 1, wherein the osteopontin is selected from the group consistingof: (a) a polypeptide comprising SEQ ID NO:1; (b) a polypeptidecomprising amino acids 1 to 168 or 170 of SEQ ID NO: 1; (c) apolypeptide comprising amino acids 1 to 16 and 170 to 314 of SEQ IDNO:1; (d) a polypeptide comprising amino acids 170 to 314 of SEQ IDNO:1; (e) a polypeptide comprising SEQ ID NO:2; (f) a polypeptidecomprising SEQ ID NO:3; (g) a mutein of any of (a) to (f), wherein theamino acid sequence has at least 40% or 50% or 60% or 70% or 80% or 90%identity to at least one of the sequences in (a) to (f); (h) a mutein ofany of (a) to (f) which is encoded by a DNA sequence which hybridizes tothe complement of the native DNA sequence encoding any of (a) to (f);(i) a mutein of any of (a) to (f) wherein any changes in the amino acidsequence are conservative amino acid substitutions to the amino acidsequences in (a) to (f); and (j) a salt or an isoform, fused protein,functional derivative, active fraction or circularly permutatedderivative of any of (a) to (f).
 9. The method according to claim 8,wherein the osteopontin is PEGylated.
 10. The method according to claim1, wherein osteopontin is fused to a carrier molecule, a peptide or aprotein that promotes the crossing of the blood brain barrier.
 11. Themethod according to claim 10, wherein the fused protein comprises animmunoglobulin (Ig) fusion.
 12. The method according to claim 1,comprising administering further an interferon, simultaneously,sequentially, or separately with respect to said administration ofosteopontin or an agonist.
 13. The method according to claim 12, whereinthe interferon is interferon-β.
 14. The method according to claim 1,wherein the osteopontin is administered in an amount of 0.001 to 100mg/kg of body weight, or 1 to 10 mg/kg of body weight, or 5 mg/kg ofbody weight.
 15. A pharmaceutical composition comprising osteopontin, oran agonist of osteopontin activity, and an interferon, optionallytogether with one or more pharmaceutically acceptable excipients, in anamount sufficient for treatment and/or prevention of a neurologicdisease.
 16. A method for treating a neurologic disease comprisingadministering to a patient in need thereof an effective amount ofosteopontin, or of an agonist of osteopontin activity, optionallytogether with a pharmaceutically acceptable carrier.
 17. A method fortreating a neurologic disease comprising administering to a patient inneed thereof an effective amount of osteopontin, or of an agonist ofosteopontin activity, and an interferon, optionally together with apharmaceutically acceptable carrier.
 18. A method for treating aneurologic disease, comprising: delivering a medicament to anappropriate site of action of the neurologic disease in a patient inneed, wherein said medicament comprises osteopontin, or an agonist ofosteopontin activity, optionally together with a pharmaceuticallyacceptable carrier.
 19. A method in accordance with claim 18, whereinsaid delivering step comprises administering said medicament.